Question

A fruit-seller had some apples. He sells $40\%$ of them and still has $420$ apples. Find the number of apples he had originally.

Answer 1

Assume that the fruit seller had $100$ apples initially.
He sell $40\%$ of them $=40$ apples
Let out apples $=(100-40)=60$
In initial amount of apples if $60$ of them are remaining $=100$
In initial amount of apples if $1$ of them is remaining $=\left(100/60\right)$
In initial amount of apples if $420$ of them are remaining $=\left(100/60\right)\times \left(420\right)$
$=(100\times 7)$
$=700$
$\therefore$ the fruit seller had $700$ apples.