Answer:
£12Step-by-step explanation:
Let Colin - x, Dan - y, David - z.
We have:
x + y + z = 20x = 2yy = 3zSubstitute and solve for z:
2y + y + z = 203y + z = 203(3z) + z = 2010z = 20z = 2Now find x and y:
y = 3*2 = 6x = 2*6 = 12Answer:
£12
Step-by-step explanation:
Let the David's money be x
If David gets = x
Dan will get = 3x
Colin gets = 3x x 2
= 6x
So, the total money can be write as
\(x + 3x + 6x = 10x\)
So, now let's find the amount of money which David have
\(10x = 20 \\ \frac{10x}{10} = \frac{20}{10} \\ x = 2\)
So, David will get £2
And now let's find the amount of money which Colin will get
\(6x = 6 \times 2 \\ = 12\)
He will get £12
Hope this helps you.
Let me know if you have any other questions :-):-)
In Dallas, Texas, 9 bats ate 45 grams of insects in one night. At this rate, how many
grams of insects could 36 bats eat in one night?
Answer:
Bats Insects(grams)
9 45g
36 X g
Unitary method :
\(X = \frac{36*45}{9} = 4*45 = 180g\)
Find domain and range of the function y=3(1/5)^x
Show your work.
A)D=(All real numbers), R= {y|y<0)
B)D=(all real numbers), R= {y|y>0)
C)D={y|y > 0}, R={x|x>0}
D) {x | x > 0 }, {all real numbers}
Answer: B) D=(all real numbers), R= {y|y>0}
Step-by-step explanation:
To find the domain and range of the function y = 3(1/5)^x, we need to analyze the behavior of the function.
Domain:
The domain of a function refers to the set of all possible input values (x-values) for which the function is defined. Since the function y = 3(1/5)^x involves an exponential expression, it is defined for all real numbers. There are no restrictions on the values of x that can be input into the function. Therefore, the domain is all real numbers.
Range:
The range of a function refers to the set of all possible output values (y-values) that the function can produce. In the case of the function y = 3(1/5)^x, we have a positive exponential decay function. This means that as x increases, the function's value (y) approaches zero, but it never actually reaches zero. Moreover, since the base (1/5) and the coefficient (3) are both positive, the function will always produce positive y-values. Therefore, the range is all positive real numbers, or {y | y > 0}.
Help with a problem I do not understand
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Answer:
\(x^2+5x+4+\dfrac{3x-8}{x^2+5x-4}\)
Step-by-step explanation:
Long Division Method of dividing polynomialsDivide the first term of the dividend by the first term of the divisor and put that in the answer.Multiply the divisor by that answer, put that below the dividend and subtract to create a new polynomial.Repeat until no more division is possible.Write the solution as the quotient plus the remainder divided by the divisor.The dividend is the polynomial which has to be divided.
The divisor is the expression by which the dividend is divided.
Given:
\(\textsf{Dividend:} \quad x^2+10x^3+25x^2+3x-24\)\(\textsf{Divisor:} \quad x^2+5x-4\)Following the steps of long division, divide the given dividend by the divisor:
\(\large \begin{array}{r}x^2+5x+4\phantom{)}\\x^2+5x-4{\overline{\smash{\big)}\,x^4+10x^3+25x^2+3x-24\phantom{)}}}\\{-~\phantom{(}\underline{(x^4+\phantom{(}5x^3-\phantom{(}4x^2)\phantom{-b)))))))))}}\\5x^3+29x^2+3x-24\phantom{)}\\-~\phantom{()}\underline{(5x^3+25x^2-20x)\phantom{)))..}}\\4x^2+23x-24\phantom{)}\\-~\phantom{()}\underline{(4x^2+20x-16)\phantom{}}\\3x-8\phantom{)}\end{array}\)
The quotient q(x) is the result of the division.
\(q(x)=x^2+5x+4\)The remainder r(x) is the part left over:
\(r(x)=3x-8\)The solution is the quotient plus the remainder divided by the divisor:
\(\implies q(x)+\dfrac{r(x)}{b(x)}=\boxed{x^2+5x+4+\dfrac{3x-8}{x^2+5x-4}}\)
Machine a can make 350 widgets in 1 hour, and machine b can make 250 widgets in 1 hour. if both machines work together, how much time will it take them to make a total of 1000 widgets?
If machine a can make 350 widgets in 1 hour and machine b can make 250 widgets in 1 hour then by forming equation we will get that both machines have to work for one hour and 40 minutes to make 1000 widgets.
Given that machine a can make 350 widgets in 1 hour, and machine b can make 250 widgets in 1 hour.
How much time will both machines take to make 1000 widgets?
Suppose the time taken by both machines be x hours. Time is equal because both the machines need to work together.
According to the question the equation will be as under:
350x+250x=1000
600x=1000
x=1000/600
x=10/6
x=5/3
x=1.67
Converting 0.67 to minutes 0.67*60=40.2
Adding will result 1 hour and 40 minutes.
Hence if machine a can make 350 widgets in 1 hour and machine b can make 250 widgets in 1 hour then by forming equation we will get that both machines have to work for one hour and 40 minutes to make 1000 widgets.
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There were 160 people who voted at the town council meeting. Of these people, 30% voted for building a new basketball court in the park. How many people voted against building the new basketball court? Complete the explanation of how to find the answer. 30% of 160 equals and 160 - - There are people that are against building the basketball court.
Answer:
there are a 112 against
Step-by-step explanation:30% of 160=48 ( 160*0.30=48)
160-48=112
A veterinarian keeps track of the types of animals treated by an animal clinic. The following distribution represents the percentages of animals the clinic has historically encountered.
If the animal clinic treats 230 animals in a month, how many of each animal type would be expected?
The expected number of each animal type treated in a month would be 69 dogs, 104 cats, 23 birds, and 35 other animals.
Define percentagePercentage is a way of expressing a number as a fraction of 100. It is denoted by the symbol "%". For example, 50% means 50 out of 100 or 0.5 as a decimal.
to find the expected number of each animal type treated in a month :
Dogs: 30% of 230 animals
= 0.30 x 230
= 69 dogs
Cats: 45% of 230 animals
= 0.45 x 230
= 103.5 cats (rounded to the nearest whole number)
Birds: 10% of 230 animals
= 0.10 x 230
= 23 birds
Other animals: 15% of 230 animals
= 0.15 x 230
= 34.5 other animals
Therefore, the expected number of each animal type treated in a month would be 69 dogs, 104 cats, 23 birds, and 35 other animals.
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sofia has a collection of 200 coins. How many coins represent 20% of her collection. Divide/scale down to solve for the missing percent.
If sofia has a collection of 200 coins, 40 coins represent 20% of Sofia's collection.
To find out how many coins represent 20% of Sofia's collection, we need to first calculate what 1% of her collection is.
To do this, we can divide the total number of coins by 100:
1% of Sofia's collection = 200 coins ÷ 100 = 2 coins
Now that we know that 1% of her collection is 2 coins, we can find 20% by multiplying 2 by 20:
20% of Sofia's collection = 2 coins × 20 = 40 coins
Therefore, 40 coins represent 20% of Sofia's collection.
To find out what percentage a different number of coins represents, we can use the same method. For example, if we want to know what percentage 30 coins represent, we can divide 30 by 2 (since 2 coins represent 1%), which gives us 15%.
So, 30 coins represent 15% of Sofia's collection.
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Which triangle congruence postulate or theorem proves that these triangles are congruent?
There are ΔABC and ΔXYZ triangles that are congruent due to the SAS congruence postulate.
What are congruent triangles?Two triangles are said to be congruent if their corresponding sides and angles are equal.
As per the given question,
In ΔABC and ΔXYZ,
Side BC = Side YZ
m∠C = m∠Z
Side AC = Side XZ
According to SAS, two triangles are congruent if the two sides and the included angle of one triangle are equal to the corresponding sides and the included angle of the other triangle.
Thus, both triangles are congruent.
Hence, there are ΔABC and ΔXYZ triangles congruent due to the SAS congruence postulate.
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Lee is forming kickball teams that include all of the students who signed up from two schools. Each team must have the same number of players and be from the same school. What is the greatest number of players Lee can put on each team?
Answer:
The answer is (12 players)
Step-by-step explanation:
2 x 2 x 3 = 12
36 - 12 = 24
The sphere has a radius of 12 inches. Find the volume.
Answer:
7238.23
Step-by-step explanation:
The magnitude of an earthquake is measured on the Richter scale as a logarithm of the intensity of the shock wave. For magnitude Rand intensity, the formula is R = log/. Using this formulo, determine how many times more intense an earthquake that measures 7.5on the Richter scale is than an earthquake which measures 2.3 on the Richter scale. Round your answer to two decimal places,
To answer this question, first, we will compute the intensity of each earthquake.
Recall that:
\(a=\log b\text{ if and only if }10^a=b.\)Therefore, using the given formula we get:
\(I=10^R.\)Then, the intensity of an earthquake that measures 7.5 on the Richter scale is:
\(I_{7.5}=10^{7.5},\)and the intensity of an earthquake which measures 2.3 on the Richter scale is:
\(I_{2.3}=10^{2.3}.\)Now, notice that:
\(\frac{I_{7.5}}{I_{2.3}}=\frac{10^{7.5}}{10^{2.3}}=10^{5.2}.\)We know that:
\(10^{5.2}\approx158489.32.\)Answer:
\(158489.32\text{ times more intense.}\)Use basic identities to simplify the expression.
1 / cot^2 theta + sec theta cos theta
Answer:
(1 / cot²θ) + secθ cosθ
(1 / cotθ) == tanθ
Therefore
tan²θ + secθ cosθ
secθ == (1 / cos θ)
Therefore
tan²θ + (1 / cosθ) cosθ
The cosθ 's cancel out
Therefore
tan²θ + 1
tan²θ + 1 == sec²θ
Therefore
sec²θ is the simplified answer
The circle graph below shows the results of a survey about the number of TV's in a household. If you surveyed 250 households, how many would you predict to have 3 TV's?
Answer: answer
Step-by-step explanation: joe nuts
Select all names that apply to the number.
3/4
A) Integer
B) Irrational
C) Whole
D) Rational
E) Real
Answer: D and E
Step-by-step explanation:
It is not an integer because it is represented by a fraction it is not an irrational number because it can be represented by the decimal 0.75. It is not a whole number because it is a fraction. It is rational because the decimal numbers do not go on forever and it is not an imaginary number so it is a real number.
Optimal Mean Estimation via Concentration Inequalities Suppose we observe a sequence of i.i.d. random variables X1, ..., Xn. Their distribution is unknown, and has unknown mean u and known variance o2. In this question, we will investigate two different estimators for the mean ti the sample mean, and the so-called "median of means" estimator. In particular, we will analyze them in terms of how many samples n are required to estimate u to a given precision e and for a confidence threshold d. We'll start with the sample mean for parts (a) - (c): in other words, we'll use X1, ..., Xn to compute an estimate Sn LiX; for the mean f. We want to see what sample size n guarantees that P(Iû – ul > e) <8. a п 12 n = (a) (2 points) Let Sn 121=1 X;. Use Chebyshev's inequality to show that n = samples are sufficient for \Sn – ul
By using Chebyshev's inequality, n = (o² * δ) / e² samples are sufficient to guarantee that P(|Sn - u| > e) < δ for the sample mean estimator.
In order to solve this question we need to consider Optimal Mean Estimation via Concentration Inequalities and use sample mean and median of means estimator.
To find the sample size n that guarantees P(|û - u| > e) < δ using Chebyshev's inequality, follow these steps:
1. Define Sn as the sample mean estimator:
Sn = (1/n) * Σ(Xi) for i = 1 to n.
2. We know the variance o² is known, and Chebyshev's inequality states that P(|X - E(X)| > k * σ) ≤ 1/k², where X is a random variable, E(X) is the expected value of X, σ is the standard deviation, and k is a constant.
3. Apply Chebyshev's inequality to Sn - u:
P(|Sn - u| > k * (o / sqrt(n))) ≤ 1/k², where k = e * sqrt(n) / o.
4. We want P(|Sn - u| > e) < δ, so we can rewrite Chebyshev's inequality as 1/k² < δ. Substitute k with e * sqrt(n) / o: 1/((e * sqrt(n) / o)²) < δ.
5. Solve for n: n = (o² * δ) / e².
By using Chebyshev's inequality, n = (o² * δ) / e² samples are sufficient to guarantee that P(|Sn - u| > e) < δ for the sample mean estimator.
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find the inverse f (x) = 8x – 5
Answer:
Step-by-step explanation:
we will replace f(x) with y
y=8x-5
x=8y-5 we solve for y
8y-5=x
y=x/8 +5/8
f^-1=x/8 +5/8
Given the following measures of the sides of triangles, which is a right triangle?
A.
10 cm, 24 cm, 26 cm
B.
13 ft, 14 ft, 15 ft
C.
7 in, 12 in, 15 in
D.
14 yd, 14 yd, 30 yd
Answer:
A
Step-by-step explanation:
10 squared + 24 squared = 26 squared :)
for a list of five positive integers, none greater than 100, the mean is 1.5 times the mode. if 31, 58, 98, $x$ and $x$ are the five integers, what is the value of $x$?
The value of x from the given five integers is 34.
Here we have to find the value of x.
Data given:
Five positive number = 31, 58, 98, x, x
The mean is 1.5 times the mode.
Mean = (31 + 58 + 98 + x + x) / 5
= (187 + 2x) / 5
Mode = x
As the mean is 1.5 times the mode so from this we have:
mean = 1.5 × mode
(187 + 2x)/ 5 = 1.5x
187 + 2x = 7.5x
5.5x = 187
x = 34
Therefore the value of x is 34.
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-11b+7=4 someone help I’ve been stuck on this problem forever
Answer: Hi!
First, we will use inverse operations to remove the 7. Subtract 7 on both sides:
7 - 7 = 0
4 - 7 = -3
Our equation now looks like this:
-11b = -3
Now we will use inverse operations to isolate the b. Divide -11 on both sides:
-11b ÷ -11 = b
-3 ÷ -11 = 3/11
Our equation now looks like this:
3/11 = b
3/11 is equal to b. This is your answer!
Hope this helps!
Suppose X is a discrete RV that takes values in (1, 2,3.,..,Suppose the PMF ofX ose the PMF of X is given by P (k) for k 1,2, 3,.. 2k a) Find and plot the CDF of X: F(x), at least up to F(X=5) for 5SK6 b) Find P(2 4) using Fx(X)
A) The CDF of X is: F(x) = 1 - 1/(x+1) for x=1,2,3,...
B)The value of function P(2 <= X <= 4) = 3/10.
a) To find the CDF of X, we need to sum up the PMF of X up to each value of k. Let's define a function f(k) as the PMF of X, which is given by:
f(k) = P(X=k) = 1/(k*(k+1))
Then, the CDF of X, denoted as F(x), is:
F(x) = P(X <= x) = sum of f(k) for k=1 to k=x
F(x) = sum of 1/(k*(k+1)) for k=1 to k=x
F(x) = sum of [1/k - 1/(k+1)] for k=1 to k=x
F(x) = [1/1 - 1/2] + [1/2 - 1/3] + ... + [1/x - 1/(x+1)]
F(x) = 1 - 1/(x+1)
Therefore, the CDF of X is:
F(x) = 1 - 1/(x+1) for x=1,2,3,...
To plot the CDF, we can use the following Python code:
import matplotlib.pyplot as plt
import numpy as np
def cdf(x):
return 1 - 1/(x+1)
x = np.arange(1, 7)
y = cdf(x)
plt.step(x, y)
plt.xlim(0, 7)
plt.ylim(0, 1.1)
plt.xlabel('x')
plt.ylabel('F(x)')
plt.title('CDF of X')
plt.show()
The plot of the CDF of X is:
CDF of X plot
b) To find P(2 <= X <= 4) using the CDF, we can use the following formula:
P(2 <= X <= 4) = F(4) - F(1)
Using the CDF we found in part (a), we have:
P(2 <= X <= 4) = F(4) - F(1) = (1 - 1/5) - (1 - 1/2) = 3/10
Therefore, P(2 <= X <= 4) = 3/10.
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Player A throws the ball to Player
B who then throws the ball the
Player C. How Far did the ball
travel given each player's position
indicated below?
Round to the nearest hundredth.
Player A: (2, 4)
Player B: (16, 9)
Player C: (25, 16)
The ball traveled approximately \(26.27\) units in total.
To calculate the distance the ball traveled, we can use the distance formula between two points in a Cartesian coordinate system.
Distance = \(\sqrt{(x_{2} - x_{1})^{2} + (y_{2} - y_{1} )^{2} }\)
Let's calculate the distance between Player A and Player B first:
Distance_AB =
\(\sqrt{((16-2)^{2}+(9-4)^{2}) }\)
\(= \sqrt{(14^{2}+5^{2} ) } \\= \sqrt{(196 +25)} \\= \sqrt{221} \\= 14.87\)
Now, let's calculate the distance between Player B and Player C:
Distance_BC =
\(\sqrt{ ((25 - 16)^2 + (16 - 9)^2)}\\= \sqrt{ (9^2 + 7^2)}\\= \sqrt{(81 + 49)}\\= \sqrt{130}\\=11.40\)
Finally, we can calculate the total distance traveled by adding the distances AB and BC:
Total distance = Distance_AB + Distance_BC
\(= 14.87 + 11.40 \\= 26.27\)
Starting from Player A at \((2, 4),\) it was thrown to Player B at \((16, 9),\) covering a distance of about \(14.87\) units. From Player B, the ball was then thrown to Player C at \((25, 16),\) covering an additional distance of approximately \(11.40\) units.
Combining these distances, the total distance the ball traveled was approximately \(26.27\) units.
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4x/x+3 + 3/x-4 = 5
Choose the possible extraneous roots. Select one or more:
a. 4 b. 0
c. -3 d. -13.21
e. 9.22
a. 4 is an extraneous root. , b. 0 is an extraneous root. , c. -3 is an extraneous root. , d. -13.21 is an extraneous root. , e. 9.22 is an extraneous root.
To solve the equation, we can begin by finding a common denominator for the fractions on the left-hand side. The common denominator is (x + 3)(x - 4). We can then rewrite the equation as follows:
[4x(x - 4) + 3(x + 3)] / [(x + 3)(x - 4)] = 5
Expanding and simplifying the numerator, we have:
[4x^2 - 16x + 3x + 9] / [(x + 3)(x - 4)] = 5
Combining like terms, we obtain:
(4x^2 - 13x + 9) / [(x + 3)(x - 4)] = 5
To eliminate the fraction, we can cross-multiply:
4x^2 - 13x + 9 = 5[(x + 3)(x - 4)]
Expanding the right-hand side, we get:
4x^2 - 13x + 9 = 5(x^2 - x - 12)
Simplifying further:
4x^2 - 13x + 9 = 5x^2 - 5x - 60
Rearranging the equation and setting it equal to zero, we have:
x^2 - 8x - 69 = 0
To solve this quadratic equation, we can factor or use the quadratic formula. Factoring the equation may not yield rational roots, so we can use the quadratic formula:
x = (-b ± √(b^2 - 4ac)) / (2a)
For the equation x^2 - 8x - 69 = 0, we have a = 1, b = -8, and c = -69. Substituting these values into the quadratic formula, we get:
x = (-(-8) ± √((-8)^2 - 4(1)(-69))) / (2(1))
= (8 ± √(64 + 276)) / 2
= (8 ± √340) / 2
= (8 ± 2√85) / 2
= 4 ± √85
So, the possible solutions for x are x = 4 + √85 and x = 4 - √85.
Now, let's check which of the given options (a, b, c, d, e) are extraneous roots by substituting them into the original equation:
a. 4: Substitute x = 4 into the equation: 4(4)/(4 + 3) + 3/(4 - 4) = 5. This results in a division by zero, which is undefined. Therefore, 4 is an extraneous root.
b. 0: Substitute x = 0 into the equation: 4(0)/(0 + 3) + 3/(0 - 4) = 5. This also results in a division by zero, which is undefined. Therefore, 0 is an extraneous root.
c. -3: Substitute x = -3 into the equation: 4(-3)/(-3 + 3) + 3/(-3 - 4) = 5. Again, we have a division by zero, which is undefined. Therefore, -3 is an extraneous root.
d. -13.21: Substitute x = -13.21 into the equation and evaluate both sides. If the equation does not hold true, -13.21 is an extraneous root.
e. 9.22: Substitute x = 9.22 into the equation and evaluate both sides. If the equation does not hold true, 9.22 is an extraneous root.
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you were in the garden, there are 34 people in the yard. you kill 30. how many people are in the garden?
In linear equation, You are the only person in the garden at the time the 34 people.
What in mathematics is a linear equation?
A linear equation is a first-order (linear) term plus a constant in the algebraic form y=mx+b, where m is the slope and b is the y-intercept.Sometimes, the aforementioned is referred to as a "linear equation of two variables," where x and y are the variables.You are the only person in the garden at the time the 34 people are on their homicidal spree.
Alternatively, if the backyard and garden are in the same place, then there are no longer any individuals in the garden because you would officially count as one of the 34 people who are all killed.
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Ramon and Hector ride their bikes at constant rates during a race. Ramon rides 45 miles in 3 hours. The distance, y, in miles, Hector rides in x hours is given by the equation y = 18x. Which statement is true?
No answer text provided.
No answer text provided.
Ramon rides his bike 3 miles per hour faster than Hector rides his bike.
Ramon rides his bike 27 miles per hour faster than Hector rides his bike.
Ramon rides his bike 3 miles per hour slower than Hector rides his bike.
Ramon rides his bike 27 miles per hour slower than Hector rides his bike.
We will find the speeds of both persons, the correct option is:
"Ramon rides his bike 3 miles per hour slower than Hector rides his bike."
Which statement is correct?First, we know that Ramon rides 45 miles in 3 hours, then its speed is:
S = 45mi/3h = 15mi/h
And we know that Hector position is given by:
y = 18x
Where x is time in hours, so his velocity is 18mi/h.
Then we can see that:
Ramon's speed = 15mi/hHector's speed = 18mi/hSo the correct statement is:
"Ramon rides his bike 3 miles per hour slower than Hector rides his bike."
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Which equation could be represented by the number line?
A. -3+(-4) = -7
B. 7+ (-6) = 1
C. 4+(-7) = -3
D. -5 + 7 = 2
Translate the sentence into an inequality.
A number y increased by 9 is less than or equal to -30.
Answer:
y + 9 ≤ -30
Step-by-step explanation:
a random sample of 20 students with scholarships is taken. what is the probability that the average scholarshi[s in the samle greater than 20,000
The probability that the average scholarshi[s in the samle greater than 20,000 is (69.729, 74.271).
Let X: Marks of students and be the population average marks.
X ~ N(72, 16)
The formula for the CI for is,
CI = mean + tₐ/₂ , ₙ₋₁ s/n
= 72 ± 2.539 × 4/20
= 72 ± (2.539 × 0.8944)
= 72 ± 2.27
= 72 - 2.27 , 72 + 2.27
= (69.729, 74.241)
Therefore, the required 98% CI for the average marks of the students is (69.729, 74.271).
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When we conclude that the results we have gathered from our sample are probably also found in the population from which the sample was drawn, we say that the results are:
When we conclude that the results we have gathered from our sample are probably also found in the population from which the sample was drawn, we say that the results are statistically significant.
In statistical analysis, we use hypothesis testing to determine whether the results of a sample are likely to be representative of the population as a whole. If the results are statistically significant, we can infer that there is a low probability that the observed differences between the sample and the population occurred by chance alone.
This allows us to generalize the findings from the sample to the larger population with a reasonable degree of confidence.
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2. It takes Jacob 30 minutes to wash the car by himself if
takes Malochi 25 minutes to wash the car by himself if
they work together, how long would it take for them to
wash the car together?
Let x represent the number of hours that he spent washing cars.
Let y represent the number of hours that he spent landscaping.
In a week, he can work no more than 19 total hours. This means that
x + y ≤ 19- - - - - - - - - - - -1
Jacob is working two summer jobs, making $10 per hour washing cars and making $8 per hour landscaping. He must earn at least $170. This means that
10x + 8y ≥ 170 - - - - - - - - - -2
If Jacob worked 4 hours landscaping, it means that
x + 4 ≤ 19 x ≤ 19 - 4 x ≤ 15
Also, 10x + 8 × 4 ≥ 170 10x + 32 ≥ 170
10x ≥ 170 - 32 10x ≥ 138
10x ≥ 138/10 x ≥ 13.8
The minimum number of hours is 14
87.20 20] Kelly made two investments totaling $5000. Part of the money was invested at 2% and the rest at 3%. In one year, these investments earned $129 in simple interest. How much was invested at each rate?
$2100 was invested at 2% and $2900 ($5000 - $2100) was invested at 3%.
Let x be the amount invested at 2% and y be the amount invested at 3%. We know that x + y = $5000 and the interest earned is $129. We can use the formula for simple interest, I = Prt, where I is the interest earned, P is the principal (or initial amount invested), r is the interest rate, and t is the time period.
Thus, we have:
0.02x + 0.03y = $129 (1)
x + y = $5000 (2)
We can solve for one of the variables in terms of the other from equation (2), such as y = $5000 - x. Substituting this into equation (1), we get:
0.02x + 0.03($5000 - x) = $129
Simplifying and solving for x, we get:
0.02x + $150 - 0.03x = $129
-0.01x = -$21
x = $2100
Therefore, $2100 was invested at 2% and $2900 ($5000 - $2100) was invested at 3%.
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