Question

If the $9 ^ { t h }$ term of an A.P. is 35 and is 75, then its terms will be.

• A. 78
• B. 79
• C. 80
• D. 81

Answer 1

Answer: (B)

79

Answer 2

$T _ { 9 } = a + 8 d = 35$ and $T _ { 19 } = a + 18 d = 75$

Solving the equations, we get $d = 4$ and $a = 3$

Hence term of A.P. $a + 19 d = 3 + 19 \times 4 = 79$.