A sample of 100 dry battery cells was tested to find the length of life. The mean life was found to be 12 hours and the standard deviation was 3…
CA Foundation · Quantitative Aptitude · MTP · September 2026
A sample of 100 dry battery cells was tested to find the length of life. The mean life was found to be 12 hours and the standard deviation was 3 hours. What percentage of battery cells are expected to have a life of less than 6 hours? (Given: Area under the normal curve from z=0 to z=2 is 0.4772.)
Suggested Answer and Working Notes:
Correct Answer: Option (A)
A. 2.28%
Topics: Part-C: Statistics
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