What will come in place of the x in the following Number series?

What will come in place of the x in the following Number series? 25, 100, x, 1600, 6400

Quiz

Answer/Solution

6400

Steps/Work

(A)
25 x 4 = 100, 100 x 4 = 400, 400 x 4 = 1600, 1600 x 4 = 6400.