Question

Compute the range and sample standard deviation for strength of the concrete​ (in psi).

39903990​,

40804080​,

34003400​,

31003100​,

29902990​,

38103810​,

40804080​,

40404040

  

The range is

10901090

psi.

sequals=nothing

psi​ (Round to one decimal place as​ needed.)

Answer 1

Sample Standard deviation, , range = max X_i - min X_i

Let X_i denote the strength of the concrete​ (in psi) for i^th sample.

Then, we can compute the following table.

Sl. No.
1	39903990	3037803.75	9.22825E+12
2	40804080	3937893.75	1.5507E+13
3	34003400	-2862786.25	8.19555E+12
4	31003100	-5863086.25	3.43758E+13
5	29902990	-6963196.25	4.84861E+13
6	38103810	1237623.75	1.53171E+12
7	40804080	3937893.75	1.5507E+13
8	40404040	3537853.75	1.25164E+13
Total	294929490	0	1.45348E+14

and

So, s= , rounded to one decimal place.

Range = 40804080 - 29902990 = 10901090