Hello,

Let X be the cost price of the article, and let Y be the price he sells the article the first time.

1st sentence

Making a profit of 25% is like selling it to 1.25 times the cost price.

So

2nd sentence

If he had bought it 20% less, it means that the cost price becomes

If he sells it for the amount 10.50 less, this means that he sells it at the price

While doing this, he makes a profit of 30%. So reasoning just as before, we get :

Now, solve for X