Question

Out of a salary of $4500. I kept 1/3 as saving. Out of the remaining money. I spend 50% on food and 20% on house rent. How much do I spend on food

Answer 1

Well 1/3 for savings means that you save 1/3*4500 or 1500 dollars.
You then have $3000 left. Of this if you spend 50% on food, you spend 0.5*3000 or 1500 dollars on food.