Question

The pulse rates of 175 randomly selected adult males vary from a low of 42 bpm to a high of 102 bpm. Find the minimum sample size required to estimate the mean pulse rate of adult males. Assume that we want 99​% confidence that the sample mean is within 4 bpm of the population mean. Complete parts​ (a) through​ (c) below. a. Find the sample size using the range rule of thumb to estimate sigma. nequals nothing ​(Round up to the nearest whole number as​ needed.)

Answer 1

Given that,

Maximum = 102

Minimum = 42

Range = maximum - minimum = 102 - 42 = 60

Using Range rule of thumb

Standard deviation = Range / 4 = 60 / 4 = 15

Population standard deviation = = 15

Margin of error = E = 4

Z_/2 = 2.576

sample size = n = [Z_/2* / E] ²

n = [2.576 * 15 / 4]²

n = 94

Sample size = n = 94