Question

sum of first twenty terms of a gp is 244 times the sum of its first ten term find common ratio

Answer 1

10*2=20
so,for first ten terms it is 244/2=122
ratio=244:122
       =2:1

Answer 2

Answer:

Step-by-step explanation:

Sn=a(r^n-1)/r-1

To find:S20=244S10

So,S10=a(r^10-1)/r-1 and S20=a(r^20-1)/r-1

S20=244*a(r^10-1)/r-1

a(r^20-1)/r-1=244* a(r^10-1)/r-1

r^20-1=244*(r^10-1)

r^10-1-244r^10+243=0

(r^10-1)(r^10-243)=0

r^10=1 or r^10=243

Therefore,r is not equal to 1

Take,r=^10=243

r^10=243

r^10=√3^10

r^10=√3