Question

find the sum of the series 5+8+11+........to 60 terms

Answer 1

This series is Arithmetic Progression (AP).
For this AP,

First Term, a = 5
Common Difference, d = 8-5 = 3
No. of terms, n = 60
Sum of first n terms, Sn

Sn = n/2 (2a + (n-1)d )
∴S₆₀ = 60/2 (2(5) + (60 - 1)*3)
         = 30 (10 + 59 * 3)
         = 30 (10 + 177)
         = 30 * 187
∴S₆₀ = 5610

Thus, sum of first 60 terms of the A.P. is 5610.

Answer 2

a = 5 d = 8-5 = 3 n = 60 Sn = n/2 (2a + (n-1)d ) ∴S₆₀ = 60/2 (2(5) + (60 - 1)*3) = 30 (10 + 59 * 3) = 30 (10 + 177) = 30× 187 ∴S₆₀ = 5610 PLZ MARK AS A BRAINLIEST. I NEEDED PLZ MARK AS A BRAINLIEST.