Published by:
CGP EDU Academic Team
Published on: August 14, 2026
The number of values of a 
N such that the variance of 3, 7, 12 a, 43 - a is a natural number is:
Text Solution
Verified by ExpertsThe correct answer is:
A
Mean =13
Variance 
2a 2 - a + 1 - 5n = 0 must have solution as natural numbers
its D = 40n - 7 always has 3 at unit place
D can't be perfect square
So, a can't be integer.
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