find the sum of first 10 terms of the A.p5+8+11using the suitable formal
Answers
Answered by
0
Answer:
Given that: a = 5, n = 15, c.d = 8 - 5 = 3
Sn=2n[2a+(n−1)d]
S15=215[2(5)+(15−1)3]=215[10+(14)(3)]=215×52
S15=390
Step-by-step explanation:
pls mark me as brainlist and like and rate
Similar questions