Question

A- The following data are the distances between 20 retail stores and a large distribution center. The distances are in miles.

29; 34; 38; 40; 58; 67; 68; 69; 76; 81; 84; 95; 96; 96; 99; 106; 112; 127; 145; 150

Use a graphing calculator or computer to find the standard deviation and round to the nearest tenth.

B-

The following data are the distances between a sample of 20 retail stores and a large distribution center. The distances are in miles.

29; 30; 31; 40; 58; 67; 68; 69; 76; 82; 85; 95; 96; 96; 99; 106; 112; 127; 145; 150

Find the value that is one standard deviation below the mean. (Round your answer to one decimal place.)

Answer 1

We calculate mean and standard deviation using R in both problems.

Ans.(A).

> x<-c(29,34,38,40,58,67,68,69,76,81,84,95,96,96,99,106,112,127,145,150)
> sd(x)
[1] 34.7313

Standard deviation () = 34.7

Ans (B).

> y<-c(29,30,31,40,58,67,68,69,76,82,85,95,96,96,99,106,112,127,145,150)
> mean(y)
[1] 83.05
> sd(y)
[1] 35.54904

Mean () =83.1

Standard deviation () = 35.5

Concept :-

and so on.