If the selling price is doubled, the profit triples. Find the profit percent.

Question: If the selling price is doubled, the profit triples. Find the profit percent.

Solution:
Let,
The cost price = x Tk
The selling price = y Tk

ATQ,
3(y - x) = 2y - x
⇒ 3y - 3x = 2y - x
⇒ 3y - 2y = - x + 3x
⇒ y = 2x

∴ Profit = y - x
= 2x - x
= x Tk

∴ Profit% = {(x/x) × 100%}
= 100%