The 3rd term of an arithmetic progression is -9 and the 7th term is -29….

The 3rd term of an arithmetic progression is -9 and the 7th term is -29. Find the 10th term of the progression

Correct Answer: Option A

Explanation

3rd term : a + 2d = -9 …….(1)
7th term : a + 6d = -29 ……(2)
(2) – (1): 4d = -20
:. d = ^-20/₄ = -5
From (1) : a + 2(-5) = -9
a – 10 = -9
:. a = -9 + 10 = 1
:. 10th term of A.P is a + 9d = 1 + 9 (-5)
= 1 – 45 = -44