The heart rate of 20 randomly selected adults was on average 85 beats per minute (bpm) with a standard deviation of 5 bpm. Build a 95% confidence interval for the mean heart rate of adults in the population. Interpret the interval you have created.

(82.66, 87.34).

Step-by-step explanation:

When population standard deviation is unknown and sample size is small , then the formula is used to find the confidence interval for is given by :-

, where n = sample size , = sample mean , t*= two tailed critical value s= sample population standard deviation, .

Given, , s=5, n=20 , degree of freedom = 19  [∵df=n-1]

For 95% confidence level ,

By t-distribution table ,

t-value for   (two tailed) and df =19 is t*=2.0930

Now , the 95% confidence interval for the mean heart rate of adults in the population will be :

Hence, the required interval is (82.66, 87.34).

Interpretation : A person can be 95% confident that the mean heart rate of adults in the population lies between (82.66, 87.34).

h

step-by-step explanation:

1. 22

2. 1

3. 7

4. 18

step-by-step explanation

e2020 got it right