Answer: D
Explanation:
Ben : 5 • x = 5x
Julie: 8 • 2x = 16x
Phil: 10 • (2x - 4) = 20x - 40
Add them all together:
5x + 16x + 20x - 40
= 41x - 40
Divide the actual building's measurements by the replica's measurements.
![\frac{400}{20}=20\\\\\frac{320}{16}=20](https://tex.z-dn.net/?f=%5Cfrac%7B400%7D%7B20%7D%3D20%5C%5C%5C%5C%5Cfrac%7B320%7D%7B16%7D%3D20)
The measurements of the actual building are divided by
20 not 12.
The crew member's calculation is
incorrect.
Answer:
a = 8
r = 15%
When t = 3, y= 4.9
Step-by-step explanation:
8 represents the original amount because that's what you're increasing, so a=8.
To find your percentage, look into the parenthesis to see the decimal. We see that it's 0.15, but that's not a percentage yet, so you have to multiply it by 100. Or, moving your decimal two times to the right. Therefore, r=15%.
Now to find what the function will equal when t=3, simply plug 3 for t. I've always used a calculator for this so I'm not going to write it out (sorry). Your result should be 4.9 (this is already rounded to the nearest tenth for you).
Answer:
, option D
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 zscore that has a pvalue of
.
From a random sample of 50 students, she found that 32 students read at least 1 book last month.
This means that ![n = 50, \pi = \frac{32}{50} = 0.64](https://tex.z-dn.net/?f=n%20%3D%2050%2C%20%5Cpi%20%3D%20%5Cfrac%7B32%7D%7B50%7D%20%3D%200.64)
90% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
Confidence interval:
![\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)
![0.64 \pm 1.645\sqrt{\frac{0.64*0.36}{50}}](https://tex.z-dn.net/?f=0.64%20%5Cpm%201.645%5Csqrt%7B%5Cfrac%7B0.64%2A0.36%7D%7B50%7D%7D)
So the correct answer is given by option D.