Question

Following are the compression breaking loads (in unit of lb) for 10 concrete cylinder tests (500, 650, 550, 530, 700, 740, 660, 810, 750, 765 lb) where each cylinder has the dimensions of 3 inches in diameter and 6 inches in length.

Determine: (1). The mean value

(2). The standard deviation

(3). The coefficient of variation

(4). The range of values with 99.7% of probability (confidence)

Answer 1

Data Given:

Results of 10 concrete test are:500, 650, 550, 530, 700, 740, 660, 810, 750, 765 lb

(1) The mean value

(2) The standard deviation

(3) The coefficient of variation

(4) The range of values with 99.7% of probability (confidence)

The range of values with 99.7% of probability is between to

= 665.5 - 3* 101.99 to 665.5+3*101.99

=665.5-305.97 to 665.5 + 305.97

=359.53lb to 971.47lb