Question

Find the sum of the first 47 terms of the following series, to the nearest integer.

9,18,27,...

Answer 1

18 is the answer hood this will help you

Answer 2

10152

Explanation:

Common difference:

18-9=9

27-18=9

d=9

Explicit formula:

an = a1 +(n-1)d

a47 = 9+ (46)(9)

a47 = 423

Find sum: Sn = n(a1+an)/2

47(9+423)/2

47(423)/2 = 20304/2 = 10152