Answer:
d. 20
Step-by-step explanation:
Standard deviation is 4.5
Margin error for the problem is 2 hours
Probability 95%, that means that the siginficance level α is 1 – p
α = 1 – 0.95 = 0.05
margin of error (ME) can be defined as follows
ME = Z(α/2) * standard deviation/ √n
Where n is the sample size
Z(0.05/2) = Z(0.025)
Using a z table Z = 1.96
Now, replacing in the equation and find n
2 = 1.96 * 4.5/ √n
2 = 8.82/√n
√n = 8.82/2
√n = 4.41
n = 4.41^2
n = 19.44 ≈ 20
Answer:

Step-by-step explanation:
for this case we have the following model for the cost of the car:

Where
is the initial amount on this case 17000, t the amount of years after the initial year and r the depreciation rate on this case:

And for t =14 we can replace into the equation and we got:

Answer:
B
Step-by-step explanation:
Matches all specified equations.
Answer:
The number of hamburgers sold was 139 and the number of cheeseburgers sold was 278.
Step-by-step explanation:
Let
x -----> the numbers of hamburgers sold on Thursday
y -----> the numbers of cheeseburgers sold on Thursday
we know that
----> equation A
----> equation B
Substitute the equation B in equation A and solve for x



Find the value of y

therefore
The number of hamburgers sold was 139 and the number of cheeseburgers sold was 278.