40% of a number is 256 then, what is 25% of this number?

Given: 

40% of a number is 256.

Solution:

Let the number be x.

​$$\frac {40}{100} \times$$ x = 256

0.4x = 256

x = $$\frac {256}{0.4}$$​​

= 640

Now, we need to calculate 25% of 640.

= $$\frac {25}{100} \times$$ 640

​

= $$\frac {1}{4} \times$$ 640

= 160

Thus, correct option is (c).