Answer:
Option c - 2402
Explanation:
Given : Samples of aluminum-alloy channels were tested for stiffness. The following frequency distribution was obtained.
To find : What is the approximate mean of the population from which the samples were taken?
Solution :
The distribution is assumed to be normal as
Stiffness(x) Frequency(f)

2480 23
2440 35
2400 40
2360 33
2320 21
Total = 152 =365040
The mean of the data is given by,



Approximately, the approximate mean of the population from which the samples were taken is 2402.
Therefore, option c is correct.