Hi Eshraj,

I am going to show you how to get started on a similar question.

Two fifths of a whole number is one less than one half of the previous whole number. Find the whole number.

Let the unknown whole number be $n$ then the previous whole number is $n - 1.$ The first sentence of the problem mentions two fifths of the whole number so that's $\large \frac25 n.$ Also one half of the previous whole number is $\large \frac12 (n - 1)$ so one less than one half of the previous whole number is $\large \frac12 (n - 1) - 1.$ Hence "Two fifths of a whole number is one less than one half of the previous whole number." becomes the equation

\[\frac25 n = \frac12 (n - 1) - 1\]

Solve for $n.$

Now try your problem and write back if you need more help,
Penny