Question

The sum of n terms of two A.Ps are in the ratio (7n-5)/(5n+17). Then which two terms of the AP series are equal?​

Answer 1

Answer:

Step-by-step explanation:

n2.[2a1+(n−1)d1]n2.[2a2+(n−1)d2]=7n−55n+17⇒2a1+(n−1)d12a2+(n−1)d2=7n−55n+27

⇒a1+(n−12)d1a2+(n−1)2d2=7n−55n+17⇒A1+5d1a2+5d2=7×11−55×11+17 [n−12=5⇒n=11]

7272=1

Hence,their 6th terms are equal.