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Assertion (A): The mean of first 'n' natural numbers is $\frac{n-1}{2}$.
Reason (R): The sum of first 'n' natural numbers is $\frac{n(n + 1)}{2}$.
Reason (R): The sum of first 'n' natural numbers is $\frac{n(n + 1)}{2}$.
- (a)Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
- (b)Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
- (c)Assertion (A) is true, but Reason (R) is false.
- (d)Assertion (A) is false, but Reason (R) is true.
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Sol. (D) Assertion (A) is false, but Reason (R ) is true (1 Mark)