Question

12) Which number replaces the question mark in the
given series?
1, 2/5, 4/25, 8/125, ?
A) 606/5
B) 10058/3
C) 3/5
D 16/625​

Answer 1

Question given :

• We need to find the number that replaces the given series of 1 , 2/5, 4/25, 8/125,

Required answer :

• $\sf\dfrac{16}{625}$ is the correct answer

Required explanation :

• Let us try to understand the given series .

That is 1 , $\sf\dfrac{2}{5}$ , $\sf\dfrac{4}{25}$ , $\sf\dfrac{8}{125}$

We come to know this that in all the following numbers the denominator is multiplied with 5 and numerator is multiplied with 2 each time . So let's confirm that we are right at this observation ,

1 × $\sf\dfrac{2}{5}$ = $\sf\dfrac{2}{5}$

$\sf\dfrac{2\:\times\:2}{5\:\times\:5}$ = $\sf\dfrac{4}{25}$

$\sf\dfrac{4\:\times\:2}{25\:\times\:5}$ = $\sf\dfrac{8}{125}$

$\sf\dfrac{8\:\times\:2}{125\:\times\:5}$ = $\sf\dfrac{16}{625}$

and so on ............