A number, when 42 is subtracted from it, reduces to its 70%. What is two-fifth of that number?

Correct option is C

Given:

A number, when 42 is subtracted from it, reduces to its 70%.

We need to find two-fifths of that number.

Solution:​
Let the number be x. According to the problem, when 42 is subtracted from x, the result is 70% of x.

x - 42 = 0.70x

x - 0.70x = 42

0.30x = 42

x =$$\frac{42}{0.30} = 140$$​

​$$\frac{2}{5} \times 140 = \frac{280}{5} = 56$$

Two-fifths of the number is 56.