(*6./Sean drives from Manchester to Gretna Green.
He drives at an average speed of 50 mph for the first 3 hours of his journey.
He then has 150 miles to drive to get to Gretna Green.
Sean drives these 150 miles at an average speed of 30 mph.
Sean says,
"My average speed from Manchester to Gretna Green was 40 mph."
Is Sean right?
You must show how you get your answer.
Answers
Sean's real average speed was less than his predicted 40 mph.
What is average speed?Calculating average speed involves dividing the whole distance traveled by the total time it took to cover that distance. Speed is the rate of movement of something at a specific time.
Student must calculate average speed, compare it to Sean's response, and determine total distance traveled and time expended. First, the formula must be stated: Average speed = Total distance traveled / Time required.We can rearrange this to determine the distance traveled.Total mileage equals time divided by average speed.We only need to compute the first leg of his travel as we already know the total distance was 150 miles. As a result, we can calculate 150 miles at 50 mph for 3 hours.We now know that the overall distance from Manchester to Greta Green was 300 miles after including the second half of the voyage.Now we have to think about how long it took overall. Rearranging the equation yields the necessary result: Time taken=distance/speed. This brings us back to the comparatively easy formula of 150 miles at 30 miles per hour equals 5 hours. This indicates that the total travel time from Manchester to Gretna Green was 8 hours, not including the initial 3 hours. We now possess all the knowledge required to calculate his average speed over the entire journey. The original equation is still used: Average speed = Total distance traveled / Time taken. After entering all the data, we get the result 300 miles in 8 hours = 37.5 miles per hour.Hence, Sean's real average speed was less than his predicted 40 mph.
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Related Questions
A high-speed bullet train accelerates and decelerates at the
rate of 10 ft/s210 ft/s2. Its maximum cruising speed is 105 mi/h105
mi/h. (Round your answers to three decimal places.)
(a) What is the max
Score on last try: 0 of 1 pts. See Details for more. You can retry this question below A high-speed bullet train accelerates and decelerates at the rate of 10 ft/s². Its maximum cruising speed is 105
Answers
A high-speed bullet train accelerates and decelerates at the rate of 10 ft/s². Its maximum cruising speed is 105 . Given information: Acceleration and deceleration rate: 10 ft/s². Maximum cruising speed: 105 mi/h.
To convert the maximum cruising speed from miles per hour to feet per second, we need to consider the conversion factors: 1 mile = 5280 feet
1 hour = 3600 seconds.
First, let's convert the maximum cruising speed from miles per hour to feet per second:105 mi/h * (5280 ft/mi) / (3600 s/h) = 154 ft/s (rounded to three decimal places). Therefore, the maximum cruising speed of the bullet train is 154 ft/s.A high-speed bullet train accelerates and decelerates at the rate of 10 ft/s210 ft/s2. Its maximum cruising speed is 105 mi/h105 mi/h.
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Please help I’m desperate fr, I hate math too
Answers
Option C is the next step to construct a congruent angle.
What is congruency?In geometry, two figures or objects are said to be congruent if their shapes and sizes match, or if one is the mirror image of the other.
Given Data
R makes the same angle with PQ and QR.
Option C is the next step to construct a congruent angle.
Steps to construct congruent triangle:
1) Each of the three sides is equal (SSS: side, side, side)
2) A comparable side and two angles are the same (ASA: angle, side, angle)
3) Both the angle between the two sides and the two sides' dimensions are equal (SAS: side, angle, side)
4) The hypotenuse, the corresponding side, and a right angle are all equal (RHS, right angle, hypotenuse, side).
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two marbles are drawn without replacement from a box with 3 white, 2 green, 2 red, and 1 blue marble. find the probability that both marbles are red.
Answers
The probability that both marbles are red is 2/14 or 1/7.
This is because there are only two red marbles in the box, so the probability of the first being drawn is 2/14 (or 1/7). Since the first marble is not replaced, the probability of the second being drawn is also 2/14 (or 1/7). Mathematically, this can be expressed as: P(Both Red) = P(Red 1) x P(Red 2) = (2/14) x (2/14) = 1/7
In general, when dealing with probability questions involving drawing multiple objects from a box, the probability of drawing one object followed by another is calculated by multiplying the probability of drawing each individual object.
In the case of two marbles being drawn without replacement, the probability of both marbles being the same color is calculated by multiplying the probability of the first marble being of that color by the probability of the second marble being of that color.
The probability of the second marble being of the same color is lower than the probability of the first marble being of that color since it is drawn from a reduced set (the original set minus the first marble).
In this case, the probability of the second marble being of the same color as the first is 2/14, or 1/7. In conclusion, the probability of both marbles being red is 2/14, or 1/7.
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A sterilization procedure yields a decimal reduction time of
0.65 minutes. Calculate the minimum sterilization time required to
yield 99.9% confidence of successfully sterilizing 50 L of medium
containing 10^6 contaminating organisms using this procedure.
Answers
The minimum sterilization time required to achieve a 99.9% confidence level in successfully sterilizing 50 L of medium containing 10^6 contaminating organisms is approximately 1.95 minutes.
To calculate the minimum sterilization time required to yield 99.9% confidence of successfully sterilizing 50 L of medium containing 10^6 contaminating organisms, we need to use the concept of decimal reduction time (D-value) and the number of organisms.
The D-value represents the time required to reduce the population of microorganisms by one log or 90%. In this case, the given D-value is 0.65 minutes.
To achieve a 99.9% confidence level, we need to reduce the population of microorganisms by three logs or 99.9%, which corresponds to a 10^-3 reduction.
To calculate the minimum sterilization time, we can use the following formula:
Minimum Sterilization Time = D-value × log10(N0/Nf)
Where:
D-value is the decimal reduction time (0.65 minutes).
N0 is the initial number of organisms (10^6).
Nf is the final number of organisms (10^6 × 10^-3).
Let's calculate it step by step:
Nf = N0 × 10^-3
= 10^6 × 10^-3
= 10^3
Minimum Sterilization Time = D-value × log10(N0/Nf)
= 0.65 minutes × log10(10^6/10^3)
= 0.65 minutes × log10(10^3)
= 0.65 minutes × 3
= 1.95 minutes
Therefore, the minimum sterilization time required to yield 99.9% confidence of successfully sterilizing 50 L of medium containing 10^6 contaminating organisms using this procedure is approximately 1.95 minutes
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Write a recursive method that computes the factorial of an input number (0! =
1! = 1, and for n > 1, n! = n ·(n −1)!). Assume that the input argument to the
method is a nonnegative integer less than 11.
Write a Java program called Factorial.java that uses your method to compute the
factorial of an input number. The input is a positive integer read from the standard
input. The output is the factorial of the input number. The output should be a
number appearing on a line by itself. Your method should take an int argument,
and return an int value.
For example, if the input is
10
then the output should be
3628800
by using Java Programming Language.
Answers
The Java program Factorial.java implements a recursive method to compute the factorial of a nonnegative integer less than 11.
The Factorial.java program in Java utilizes a recursive method to calculate the factorial of a given number. The recursive method follows the mathematical definition of factorial, where the factorial of a number n is n multiplied by the factorial of (n-1). The program first checks if the input number is within the valid range (0 to 10). If it is, the program calls the recursive method to calculate the factorial. The base case of the recursive method is when the input number is 0 or 1, where the factorial is defined as 1. For any other number, the method recursively calls itself with the number decreased by 1 until it reaches the base case. The factorial value is calculated by multiplying the current number with the factorial of the decreased number. Finally, the program displays the computed factorial as output.
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The table shows the total number y (in billions) of U.S. movie admissions each year for x years. Use a graphing calculator to find an equation of the line of best fit for the data. Round each value to the nearest hundredth.
The line of best fit is y = _
(I need this by 11 pm please)
Answers
Answer:
By rounding up of the constant and coefficient terms, we have;
The line of best, fit is y = 1.23 + 3.46 × 10⁻²·x
Step-by-step explanation:
The table for the data on the number of movie admissions each year is presented as follows;
Year, x \({}\) Admission, y
0 \({}\) 1.24
2 \({}\) 1.26
4 \({}\) 1.39
6 \({}\) 1.47
8 \({}\) 1.49
10 \({}\) 1.57
Using a graphing calculator, we have that the line of best fit is given by the following equation;
y = 1.23047619048 + 3.45714285714 × 10⁻²·x
Which is approximately, y = 1.23 + 3.46 × 10⁻²·x
Pls help with the question (also lmk how to award brainliest and I will)
Answers
4. (-3,-4)
Explanation:
Both coordinates will be located in the third quadrant.
The mean time required to repair breakdowns of a certain copying machine is 93 minutes. The company which manufactures the machines claims that breakdowns of its newer model are easier to fix. To test this claim, a sample of 18 breakdowns of the new model were observed, resulting in a mean repair time of 86.8 minutes with a standard deviation of 14.6 minutes. Using a significance level of a = 0.10, determine if the new copy machines are faster to repair. State clearly what your null and alternative hypotheses are, show your work, and state your conclusion.
Answers
A significance level of 0.10, we have enough evidence to conclude that the new copy machines have a significantly faster mean repair time compared to the older model.
To test if the new copy machines are faster to repair, we can set up the following null and alternative hypotheses:
Null Hypothesis (H₀): The mean repair time for the new copy machines is the same as the mean repair time for the older model.
Alternative Hypothesis (H₁): The mean repair time for the new copy machines is less than the mean repair time for the older model.
Let's perform a one-sample t-test to test these hypotheses. The test statistic is calculated as:
t = (sample mean - population mean) / (sample standard deviation / √(sample size))
Given:
Population mean (μ) = 93 minutes
Sample mean (\(\bar x\)) = 86.8 minutes
Sample standard deviation (s) = 14.6 minutes
Sample size (n) = 18
Significance level (α) = 0.10
Calculating the test statistic:
t = (86.8 - 93) / (14.6 / sqrt(18))
t = -6.2 / (14.6 / 4.24264)
t ≈ -2.677
The degrees of freedom for this test is n - 1 = 18 - 1 = 17.
Now, we need to determine the critical value for the t-distribution with 17 degrees of freedom and a one-tailed test at a significance level of 0.10. Consulting a t-table or using statistical software, the critical value is approximately -1.333.
Since the test statistic (t = -2.677) is less than the critical value (-1.333), we reject the null hypothesis.
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Slope is 2/5. How would you plot your points? *
Select all that apply.
O go up 2 then to the right 5
O go down 2 then to the left 5
O go up 2 then to the left 5
O go down 2 then to the right 5
Answers
The line goes up by 2 then to the right by 5.
Given,
slope =\(\frac{2}{5}\)
General form of slope
\(slope=\frac{change\ in\ y}{change\ in\ x}\)
Here the given slope is positive
change in y, △y=2
change in x, △x=5
So, the △y goes up by 2 units and then △x goes to right by 5 units.
Hence, the line goes up by 2 units then to the right by 5 units.
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maggie is stocking up on chicken noodle soup for the winter season. if each can is 1.25 and she has a $2 coupon, how many cans ca she buy if she can spend no more than $30?
Answers
Answer:
25 cans
Step-by-step explanation:
i need help with this
Answers
Part A:
The scale of the line plot should have 0 as its least data value and 4 as its greatest data value.
Part B:
There will be 11 dots above 1.
There will be 6 dots above 4.
There will be three dots above 3.
What is a line plot?A line plot, also known as a dot plot, is a type of graph that is used to display and organize small sets of data.
It consists of a number line with dots or Xs placed above each value to represent the frequency or count of that value in the data set.
Line plots are useful for quickly visualizing the distribution of data and identifying the most common values or outliers.
They are especially helpful when the data set is small and discrete, meaning that the values are distinct and separate, rather than continuous.
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I just want the coordinates, thanks :)
Answers
youre welcome !!
Answer:
(0,1) and (1,4)
Step-by-step explanation:
what is the value of 8n when n=2
Answers
Answer:
16
Step-by-step explanation:
8(2) = 16
Answer:
16
Step-by-step explanation:
Explain why the following form linearly dependent sets of vec- tors. (Solve this problem by inspection.) (a) uj = (-1, 2, 4) and u2 = (5, –10, –20) in R3 (b) u = (3, -1), u2 = (4, 5), uz = (-4, 7) in R2 (c) pı = 3 – 2x + x2 and p2 = 6 – 4x + 2x2 in P2 _3 4 3 -4 (d) A = and B= | in M22
Answers
(a) This can be seen by multiplying u1 by -5 and comparing it to u2: -5u1 = (5, -10, -20), which is equal to u2. (b) This can be seen by adding u1 and u2 together and comparing it to u3: u1 + u2 = (7, 4) and u3 = (-4, 7), which are equal. (c) This can be seen by multiplying p1 by 2 and comparing it to p2: 2p1 = 6 - 4x + 2x², which is equal to p2. (d) A and B are not scalar multiples of each other and are linearly independent.
(a) The two vectors u1 and u2 are linearly dependent because u2 is equal to -5 times u1. This can be seen by multiplying u1 by -5 and comparing it to u2: -5u1 = (5, -10, -20), which is equal to u2.
(b) The three vectors u1, u2, and u3 are linearly dependent because u3 is equal to the sum of u1 and u2. This can be seen by adding u1 and u2 together and comparing it to u3: u1 + u2 = (7, 4) and u3 = (-4, 7), which are equal.
(c) The two polynomials p1 and p2 are linearly dependent because p2 is equal to twice p1. This can be seen by multiplying p1 by 2 and comparing it to p2: 2p1 = 6 - 4x + 2x², which is equal to p2.
(d) The two matrices A and B are linearly independent because they have different determinants. The determinant of A is -15 and the determinant of B is 16, which are not equal. Therefore, A and B are not scalar multiples of each other and are linearly independent.
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The bottlers of the new soft drink "Guzzle" are experiencing problems with the filling mechanism for their 16oz bottles. To estimate the population standard deviation of the volume, the filled volume for 20 bottles was measured, yielding a sample standard deviation of 0.1oz. Compute a 95% confidence interval for the standard deviation; assuming normality.
Answers
The required answer is the filled volume for "Guzzle" bottles is between 0.0054oz and 0.0197oz.
Based on the given information, the bottlers of "Guzzle" are experiencing issues with the filling mechanism for their 16oz bottles. To estimate the population standard deviation of the volume, the filled volume for 20 bottles was measured, yielding a sample standard deviation of 0.1oz.
To compute a 95% confidence interval for the standard deviation, we can use the formula:
CI = ( (n-1) * s^2 / X^2_α/2, (n-1) * s^2 / X^2_1-α/2 )
Where CI is the confidence interval, n is the sample size (in this case, 20), s is the sample standard deviation (0.1oz), X^2_α/2 is the chi-squared value for the upper tail of the distribution with α/2 degrees of freedom (where α = 0.05 for a 95% confidence interval), and X^2_1-α/2 is the chi-squared value for the lower tail of the distribution with 1-α/2 degrees of freedom.
Using a chi-squared table or calculator, we can find that X^2_α/2 = 31.410 and X^2_1-α/2 = 10.117.
Plugging in the values, we get:
CI = ( (20-1) * 0.1^2 / 31.410, (20-1) * 0.1^2 / 10.117 )
Simplifying, we get:
CI = (0.0054, 0.0197)
Therefore, we can say with 95% confidence that the population standard deviation of the filled volume for "Guzzle" bottles is between 0.0054oz and 0.0197oz.
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here is the gauge for the fuel tank of a car.the tank holds 68 litres when the tank is full. the tank is 1/4 full of fuel work out how many more litres of fuel is needed to fill the tank
Answers
Answer:
51 liters of fuel is needed more to fill the tank
Step-by-step explanation:
When the gauge is full, the volume of fuel in the tank is 68 liters.
Now it is 1/4 full.
The amount of fuel it has when it is 1/4 full would be 1/4 * 68 = 17 liters
Now, we need to know how many more liters of fuel until the tank is full.
What we just need to do here is to subtract the volume when it is quarter full from the volume when it is full.
That would be 68 liters - 17 liters = 51 liters
Evaluate the series 1 + 2 + 4 + 8 to S10.
Answers
The series to 10 term is
1 + 2 + 4 + 8 + 16 + 32 + 64 + 128 + 256 + 512
What is recurrent relation?An equation that represents a sequence based on a rule is called a recurrence relation.
Finding the following term, which is dependent upon the prior phrase, is made easier (previous term). We can readily predict the following term in a series if we know the preceding term.
The term is predicted by multiplying the preceding term by 2
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What is a polynomial with more than 3 terms read with
Answers
A polynomial more than 3 terms is read as trinomial.
What is polynomial?A polynomial is an equation that solely uses the operations of addition, subtraction, multiplication, and non-negative integer exponentiation of variables. Variables are also known as indeterminates.
Sums of terms of the form kxn, where k is any number and n is a positive integer, make up polynomials. For instance, the polynomial 3x+2x-5. a description of polynomials.
hence, a polynomial more than 3 is trinomial or cubic.
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What is the solution to the system of equations?
3x − 6y = −12
−x + 2y = 8
Answers
-x+2y=8 the answer is y= 4+x/2 but u didn’t say solve for what so I solve for y this time
the weight w of a steel frame is 9.2kg correct to 1 decimal place. complete the error interval for weight w
Answers
Answer:
9.5_<w<9.25
Step-by-step explanation:
Samantha's salary is $54,000 per year. Her car payment totals $3,600 0/ per year. What percent of her salary is spent on car payments? Round to the nearest tenth percent. Be sure to include a % sign.
Answers
= 3600 / 54000
= 0,06666
x 100
≈ 6,7%
In large restaurant an average of3 out every 5 customers ask water with their meal. Random sample of 10 customers were selected. What is the probability that exactly 6patients at least 2 patients
Answers
The probability that exactly 6 patients is 2.0669, and the probability that at least 2 patients is 0.0017.
In large restaurants, an average of 3 out of every 5 customers ask for water with their meal. A random sample of 10 customers was selected. We need to estimate the probability that exactly 6 patients and at least 2 patients. The given situation is a binomial distribution since the experiment has only two outcomes, success or failure.
Here, Success is defined as requesting water with a meal, and failure as not requesting water with a meal. The probability of success is p = 3/5 = 0.6 and the probability of failure is q = 1 - p = 1 - 0.6 = 0.4. Let X be the number of patients requesting water with a meal out of 10 patients selected.
P(X = 6) = 10C6 (0.6) (0.4)⁴
= 210 × 0.31104 × 0.0256
= 2.0669P(X ≥ 2)
= P(X = 2) + P(X = 3) + .... + P(X = 10)P(X ≥ 2)
= 10C2 (0.6)² (0.4)⁸ + 10C3 (0.6)³ (0.4)⁷ + ..... + 10C10 (0.6)¹⁰ (0.4)⁰ P(X ≥ 2)
= 0.0022 + 0.0185 + 0.0881 + 0.2353 + 0.3454 + 0.2508 + 0.0986 + 0.0180 + 0.0016P(X ≥ 2)
= 1 - P(X < 2)P(X < 2) = P(X = 0) + P(X = 1)P(X < 2)
= 10C0 (0.6)⁰ (0.4)¹⁰ + 10C1 (0.6)¹ (0.4)⁹ P(X < 2)
= 0.0001 + 0.0016P(X < 2)
= 0.0017
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Reduce the third order ordinary differential equation y-y"-4y +4y=0 in the companion system of linear equations and hence solve Completely. [20 marks]
Answers
To reduce the third-order ordinary differential equation y - y" - 4y + 4y = 0 into a companion system of linear equations, we introduce new variables u and v:
Let u = y,
v = y',
w = y".
Taking the derivatives of u, v, and w with respect to the independent variable (let's denote it as x), we have:
du/dx = y' = v,
dv/dx = y" = w,
dw/dx = y"'.
Now we can rewrite the given differential equation in terms of u, v, and w:
u - w - 4u + 4u = 0.
Simplifying the equation, we get:
-3u - w = 0.
This equation can be expressed as a system of first-order linear differential equations as follows:
du/dx = v,
dv/dx = w,
dw/dx = -3u - w.
Now we have a companion system of linear equations:
du/dx = v,
dv/dx = w,
dw/dx = -3u - w.
To solve this system completely, we need to find the solutions for u, v, and w. By solving the system of differential equations, we can obtain the solutions for u(x), v(x), and w(x), which will correspond to the solutions for y(x), y'(x), and y"(x), respectively.
The exact solutions for this system of differential equations depend on the initial conditions or boundary conditions that are given. By applying appropriate initial conditions, we can determine the specific solution to the system.
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The working out aswell please.
Answers
Answer:
2/55 < 1/27 < 0.038 < 5^-2
Step-by-step explanation:
5^-2 = 0.040
1/27 = 0.037
2/55 ≈ 0.036
0.038 = 0.038
0.036, 0.037, 0.038, 0.040
2/55, 1/27, 0.038, 5^-2
suppose there are 20 computer chips if 95% of the chips work what is the probability that exactly 8 work
Answers
The probability that exactly 8 work out of 20 computer chips is found to be 0.1 using Binomial probability distribution.
For each chip, there are only two possible outcomes. Either it works, or it does not. The chips work independently of one another. So we use the binomial probability distribution to solve this question.
Binomial probability distribution :
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
P(X = x) = C{n,x}.p^x.(1-p)^n-x
In which C{n,x} is the number of different combinations of x objects from a set of n elements, given by the following formula.
C{n,x} = n! /x! (n-x)!
And p is the probability of x happening.
so the probability that exactly 8 work is given by P(X= 8).
95% of the computer chips work properly , p =0.95
P(X= 8) = C{20,8}.0.95^20.(0.05)^12
= 0.1
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The complete question is :
Suppose that 20 computer chips are randomly selected from a large shipment. If 95% of the computer chips work properly, and each chip works independently of one another, what is the probability that exactly 8 of the chips work?
How do you express 0.000 000 000 000 1 in exponential form.
Answers
Answer:
1 x 10^-12
Step-by-step explanation:
....
Find the side length of the regular octagon whose perimeter is 674 units.
Answers
Answer:
Solving for A.
8 = 1
Step-by-step explanation:
a=P
8=674
8=84.25
Find the indefinite integral and check the result by differentiation. (use c for the constant of integration.) x(5x2 5)9 dx
Answers
The indefinite integral of x(5x^2 - 5)^9 dx is:
(5x^2 - 5)^8 / 40 + c
We can find the indefinite integral using the following steps:
1. We can write the integral as (5x^2 - 5)^9 * x^1 dx.
2. We can use the power rule of integration, which states that the integral of x^n dx is x^(n + 1) / (n + 1) + c, where c is the constant of integration.
3. We can simplify the result and add the constant of integration.
The following is the step-by-step solution:
```
∫ x(5x^2 - 5)^9 dx = ∫ (5x^2 - 5)^9 * x^1 dx
= (5x^2 - 5)^9 / 9 + c
```
To check the result, we can differentiate the result and see if we get the original integral.
```
d/dx [(5x^2 - 5)^8 / 40 + c] = (5x^2 - 5)^8 * (10x) / 40 + 0 = x(5x^2 - 5)^8 = ∫ x(5x^2 - 5)^9 dx
```
As we can see, we get the original integral back. Therefore, the answer is correct.
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A number is 3 times another. Theirs sum is 64. What are the numbers?
Answers
Answer:
x = 16
Step-by-step explanation:
x + 3*x = 64
x + 3x = 64
4x = 64
/4 /4
x = 16
Check:
x + 3*x = 64
16 + 3(16) = 64
16 + 48 = 64
64 = 64
Hope this helps!
Answer:
16 + 48 = 64
Step-by-step explanation:
In a recent experiment conducted by the Department of Energy, light bulbs were tested to measure how long they lasted. Each company submitted 20 light bulbs, which were turned on and left on until they burned out. Here were the results:
-All 20 "Super Bright" light bulbs burned out after exactly 1,500 hours.
-The first "Delightful Bright" light bulb burned out after 1,200 hours, and one additional bulb burned out every 50 hours until they were all burned out.
-One of the "Pretty Bright" light bulbs burned out after just 16 hours. The other 19 bulbs lasted between 1,900 and 2,000 hours.
Which of the following is true?
Choose all answers that apply:
A. Super Bright and Pretty Bright light bulbs cannot possibly have the same mean light bulb life.
B. The interquartile range of light bulb life for Delightful Bright is greater than the interquartile range for Pretty Bright.
C. The distribution of Delightful Bright light bulb life is skewed right.
D. Super Bright light bulbs have the smallest standard deviation for light bulb life among the three types of bulbs.
Answers
The correct options regarding the distributions are given as follows:
A. Super Bright and Pretty Bright light bulbs cannot possibly have the same mean light bulb life.
B. The interquartile range of light bulb life for Delightful Bright is greater than the interquartile range for Pretty Bright.
D. Super Bright light bulbs have the smallest standard deviation for light bulb life among the three types of bulbs.
MeanThe mean of a distribution is given by the sum of all observations divided by the number of observations.
For the Super Bright light builds, the mean is given as follows:
Ms = 20 x 1500/20 = 1,500 hours.
For the Pretty Bright lights, the minimum mean is given as follows:
Mp = (16 + 19 x 1900)/20 = 1,805.8 hours
This mean is greater than 1,5000 hours, hence option A is correct.
Interquartile rangeThe interquartile range (IQR) of a distribution is given by the difference between the third quartile and the first quartile of a distribution.
For each distribution, the IQR is given as follows:
Super Bright: 0. (all at 1500).Delightful Bright: 500. (difference of 50 between the 5th observation and the 15th observation).Pretty Bright: less than 100, as the outlier does not count for the IQR.Skewness of Delightful BrightThe delighful bright distribution has a constant increase of 50 in the duration of each bulb, hence the distribution is symmetric around the mean and option c is incorrect.
Standard deviationThe standard deviation is given by the square root of the sum of the differences squared between each observation and the mean.
Since the Super Bright measures are all equal, their standard deviation has the lowest possible value, and option D is correct.
More can be learned about distributions at https://brainly.com/question/28939231
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