Answer: 4/5
Step-by-step explanation:
80% is 80/100
80/100 simplified is 4/5
Answer:
a. n=4148
b. n=3909
c. The sample size is smaller if a known proportion from prior study is used. The difference in sample sizes is 239
Step-by-step explanation:
a. For sample where no preliminary estimate is given, the minimum sample size is calculated using the formula:
![n=p(1-p)(\frac{z}{ME})^2](https://tex.z-dn.net/?f=n%3Dp%281-p%29%28%5Cfrac%7Bz%7D%7BME%7D%29%5E2)
Where:
Margin of error
is the assumed proportion
#Let p=0.5, substitute in the formula to solve for n:
![n=0.5(1-0.5)\times (2.576/0.02)^2\\\\=4147.36\approx 4148](https://tex.z-dn.net/?f=n%3D0.5%281-0.5%29%5Ctimes%20%282.576%2F0.02%29%5E2%5C%5C%5C%5C%3D4147.36%5Capprox%204148)
Hence, the minimum sample size is 4148
b. If given a preliminary estimate p=0.38, we use the same formula but substitute p with the given value:
![n=p(1-p)(z/ME)^2\\\\=0.38(1-0.38)(2.576/0.02)^2\\\\=3908.47\approx3909](https://tex.z-dn.net/?f=n%3Dp%281-p%29%28z%2FME%29%5E2%5C%5C%5C%5C%3D0.38%281-0.38%29%282.576%2F0.02%29%5E2%5C%5C%5C%5C%3D3908.47%5Capprox3909)
Hence, the minimum sample size is 3909
c. Comparing the sample sizes from a and b:
![n_{0.5}>n_{0.38}\\\\n_{0.5}-n_{0.38}=4148-3909=239](https://tex.z-dn.net/?f=n_%7B0.5%7D%3En_%7B0.38%7D%5C%5C%5C%5Cn_%7B0.5%7D-n_%7B0.38%7D%3D4148-3909%3D239)
Hence, the actual sample size is smaller for a known proportion from prior a prior study.
Formula : Amount of change / Original amount
1. 144 - 90/ 144
2. Subtract 144 and 90
3. 54/ 144
4. Divide 54 by 144
5 0.375
6 Move the decimal two places to the right.
7. 37.5 %
Answer: 37.5% is the markup rate
Answer: 9/15 < 10/15
Step-by-step explanation: 9/15 < 10/15