We know, nth term of an AP = Sum of n terms - Sum of (n-1) terms
Therefore, nth term = \(n(n+1) - (n-1)(n) = n^2 + n - n^2 + n = 2n\)
Given, nth term is divisible by 7. So, 2n must be divisible by 7.
For 2n to be divisible by 7, the smallest possible value of n is when \(2n = 7\times2 = 14.\)
Therefore, n = 7.
Directions: In Question Numbers 19 and 20, a statement of Assertion (A) is followed by a statement of Reason (R).
Choose the correct option from the following:
(A) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
(B) Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).
(C) Assertion (A) is true, but Reason (R) is false.
(D) Assertion (A) is false, but Reason (R) is true.
Assertion (A): For any two prime numbers $p$ and $q$, their HCF is 1 and LCM is $p + q$.
Reason (R): For any two natural numbers, HCF × LCM = product of numbers.