Question

The sum of the first 20 terms of the sequence an=7n+2 is

Answer 1

Sum of the first 20 terms = 1510

Explanation:

a₂₀ = 7*20 + 2 = 142

This is an Arithmetic progression, a = 9, last term = 142

Sum of the 20 terms using: n/2(a + l) where l = last term.

= 20/2(9 + 142)

= 10 * 151

1510 hope ths helps