The number of positive integers n in the range 12 ≤ n ≤ 40 such that the product (n − 1)(n − 2)...3.2.1 is not divisible by n is
Explanation:
For (n − 1)(n − 2) … 3.2.1 to not be divisible by n, n should be a prime number.
But, there are 7 prime numbers in the range 12 ≤ n ≤ 40 are 7.
The prime numbers are 13, 17, 19, 23, 29, 31, 37.
Hence, option (b).
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