Sabine records the daily heights of a random sample of bamboo stalks, in inches. They are:

Answer:

Step-by-step explanation:

13.71

Step-by-step explanation:

Provided the values: 13, 17, 9, 21

Calculating the average of the values;

total of the data =13+17+9+21=60

Count of the data, n, = 4

Average= total/n =60/4 =15

Calculating the variation from the average

13-4=9

17-4=13

9-4=5

21-4=17

Squaring the variations from average

9²=81

13²=169

5²=25

17²=289

Summing the squares of variations from average

81+169+25+289 =564

Determining n-1

4-1=3

Calculating variance

564/3 =188

Calculating the standard deviation

√188 = 13.71

Response:

sample variance: choice A

sample standard deviation: choice B

Detailed explanation:

To assess a sample, we require the formula for sample variance and the calculation for sample standard deviation. Calculating the standard deviation involves taking the square root of the variance. For sample , the sample mean is applied, rather than , which represents the population mean.