Answer:
32m
Step-by-step explanation:
3m(4 + 7) - m
~Use distributive property to simplify
12m + 21m - m
~Combine like terms
33m - m
32m
Best of Luck!
Answer:
Regular price of 1 pizza = $15 {Assuming discount coupon = $22.5}
Step-by-step explanation:
Let regular non discounted price of 7 pizzas be x
x - 22.5 = 82.5
x = 82.5 + 22.5
x = 105 (Regular Non discounted price of 7 pizzas)
Regular Price of 7 pizzas = 105
Regular price of 1 pizza = 105 / 7 = 15
Answer:
A sample of 752 should be taken.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.
![\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}](https://tex.z-dn.net/?f=%5Cpi%20%5Cpm%20z%5Csqrt%7B%5Cfrac%7B%5Cpi%281-%5Cpi%29%7D%7Bn%7D%7D)
In which
z is the z-score that has a p-value of
.
The margin of error is of:
![M = z\sqrt{\frac{\pi(1-\pi)}{n}}](https://tex.z-dn.net/?f=M%20%3D%20z%5Csqrt%7B%5Cfrac%7B%5Cpi%281-%5Cpi%29%7D%7Bn%7D%7D)
90% confidence level
So
, z is the value of Z that has a p-value of
, so
.
No preliminary sample is taken
This means that ![\pi = 0.5](https://tex.z-dn.net/?f=%5Cpi%20%3D%200.5)
How large should the sample be to be 90% sure that the estimate is within .03 of the population proportion?
This is n for which M = 0.03. So
![M = z\sqrt{\frac{\pi(1-\pi)}{n}}](https://tex.z-dn.net/?f=M%20%3D%20z%5Csqrt%7B%5Cfrac%7B%5Cpi%281-%5Cpi%29%7D%7Bn%7D%7D)
![0.03 = 1.645\sqrt{\frac{0.5*0.5}{n}}](https://tex.z-dn.net/?f=0.03%20%3D%201.645%5Csqrt%7B%5Cfrac%7B0.5%2A0.5%7D%7Bn%7D%7D)
![0.03\sqrt{n} = 1.645*0.5](https://tex.z-dn.net/?f=0.03%5Csqrt%7Bn%7D%20%3D%201.645%2A0.5)
![\sqrt{n} = \frac{1.645*0.5}{0.03}](https://tex.z-dn.net/?f=%5Csqrt%7Bn%7D%20%3D%20%5Cfrac%7B1.645%2A0.5%7D%7B0.03%7D)
![(\sqrt{n})^2 = (\frac{1.645*0.5}{0.03})^2](https://tex.z-dn.net/?f=%28%5Csqrt%7Bn%7D%29%5E2%20%3D%20%28%5Cfrac%7B1.645%2A0.5%7D%7B0.03%7D%29%5E2)
![n = 751.7](https://tex.z-dn.net/?f=n%20%3D%20751.7)
Rounding up:
A sample of 752 should be taken.
Answer:
$21.2
Step-by-step explanation:
cost without tax=$20
$20x106%=21.2