Question

Find the 8^th term from the end of the A.P. 7, 10, 13,....., 184

Answer 1

a = 7, d = 3

Last term, a_n = 184

a_n = a + (n – 1) d

184 = 7 + (n - 1) 3

184 = 7 + 3n – 3

180 = 3n

n = 60

Now we have to find last 8^th term, it means = 60^th – 7 = 53^rd term

a₅₃ = 7 + (53 – 1)3

= 7 + 52 x 3

= 7 + 156 = 163

Hence, 8^th term from the end of given is 163