Question

An A.P. consists of 60 terms, If the first and the last terms be 7 and 125 respectively, find the 31^st term.

Answer 1

For a given A.P.,

Number of terms, n = 60

First term, a = 7

Last term, l = 125

`\implies` t₆₀ = 125

`\implies` a + 59d = 125

`\implies` 7 + 59d = 125

`\implies` 59d = 118

`\implies` d = 2

Hence, t₃₁ = a + 30d

= 7 + 30(2)

= 7 + 60

= 67