Question

Find the common ratio of the GP 25, −5, 1, −1/5.

Answer 1

In the given G.P.

First term (a)=25

We know that

tn=a*r^n-1

=>t2=a*r

=>t2=-5=25*r

=> -5=25*r

=> r= -1/5

Thus the common ratio is (-1/5).

Thanks!!!

Answer 2

Answer:

-1/5

Step-by-step explanation:

In a Geometric Progression, a certain term is always multiplied with the common ratio (r, say) to get the next term.

Hence, if the first term is a, then the series will be  

a, ar, ar², ar³,.....

Now, in the given series 25, -5, 1, -1/5  

a= 25, ar= -5, ar² =1, ar³ =-1/5

Now, ar/a =-5/25 =-1/5 =r

Hence, the common ratio of the G.P. series is -1/5. (Answer)