Testing random samples of lightbulbs produced by a company to confirm they work and testing a new drug on a random sample of patients to see how effective it is at curing the flu are examples of inferential statistics. The correct option among all the options that are given in the question are option "C" and option "E".
Answer:
Step-by-step explanation:
Answer: 72.78% of the drivers are traveling between 70 and 80 miles per hour based on this distribution.
Step-by-step explanation:
Let X be a random variable that represents the speed of the drivers.
Given: population mean : M = 72 miles ,
Standard deviation: s= 3.2 miles
The probability that the drivers are traveling between 70 and 80 miles per hour based on this distribution:
![P(70\leq X\leq 80)=P(\frac{70-72}{3.2}\leq \frac{X-M}{s}\leq\frac{80-72}{3.2})\\\\= P(-0.625\leq Z\leq 2.5)\ \ \ \ \ [Z=\frac{X-M}{s}]\\\\=P(Z\leq2.5)-P(Z\leq -0.625)\\\\\\ =0.9938-0.2660\ \ \ [\text{Using p-value calculator}]\\\\=0.7278](https://tex.z-dn.net/?f=P%2870%5Cleq%20X%5Cleq%2080%29%3DP%28%5Cfrac%7B70-72%7D%7B3.2%7D%5Cleq%20%5Cfrac%7BX-M%7D%7Bs%7D%5Cleq%5Cfrac%7B80-72%7D%7B3.2%7D%29%5C%5C%5C%5C%3D%20P%28-0.625%5Cleq%20Z%5Cleq%202.5%29%5C%20%5C%20%5C%20%5C%20%5C%20%5BZ%3D%5Cfrac%7BX-M%7D%7Bs%7D%5D%5C%5C%5C%5C%3DP%28Z%5Cleq2.5%29-P%28Z%5Cleq%20-0.625%29%5C%5C%5C%5C%5C%5C%20%3D0.9938-0.2660%5C%20%5C%20%5C%20%5B%5Ctext%7BUsing%20p-value%20calculator%7D%5D%5C%5C%5C%5C%3D0.7278)
Hence, 72.78% of the drivers are traveling between 70 and 80 miles per hour based on this distribution.
B.4
1/4 divided by 2
do the reciprocal
1/4 times 1/2=2/8
divide 8by 2