Question

g The tensile 0.2 percent offset yield strength of AISI 1137 cold-drawn steel bars up to 1 inch in diameter from 2 mills and 25 heats is reported as follows: S y 93 95 97 99 101 103 105 107 109 111 f 19 25 38 17 12 10 5 4 4 2 where y S is the class midpoint in kpsi and f is the number in each class. Presuming the distribution is normal, what is the yield strength exceeded by 99 percent of the population

Answer 1

Answer:

107.50

Step-by-step explanation:

Given the following :

Midpoint (S)____F

S y 93 95 97 99 101 103 105 107 109 111 f 19 25 38 17 12 10 5 4 4 2

Calculating the mean and standard deviation using a calculator :

The mean(m) of the data above = 98.12

Standard deviation (sd) = 4.02

Proportion = 99% of population

From z table = 2.33

Using :

Zscore =(x - m) / sd

2.33 = (x - 98.12) / 4.02

2.33 * 4.02 = x - 98.12

9.3666 = x - 98.12

9.3666 + 98.12= x

x = 107.4866

X = 107.50