Question

The n^th term of the series 3 + 10 + 17 + ….. and 63 + 65 + 67 + …… are equal, then the value of n is

• A. 11
• B. 12
• C. 13
• D. 15

Answer 1

Answer: (C)

13

Answer 2

n^th term of 1^st series $= 3 + (n - 1)7 = 7n - 4$

n^th term of 2^nd series$= 63 + (n - 1) = 2n + 61$

∴ we have, $7n - 4 = 2n + 61$ ⇒ n = 13