To find the profit percentage when the selling price is doubled and the profit triples, let's use the following steps:
Let the cost price be \( C \) and the original selling price be \( S \). The original profit is \( S - C \).
When the selling price is doubled, it becomes \( 2S \). The new profit is thus \( 2S - C \).
According to the problem, the new profit is triple the original profit. Hence, we have the equation: \( 2S - C = 3(S - C) \).
Expanding and simplifying the equation, we have: \(2S - C = 3S - 3C\) \(2S - C = 3S - 3C\) Add \( 3C \) and subtract \( 2S \) from both sides: \(3C - C = 3S - 2S\) \(2C = S\)
Now, the original selling price \( S = 2C \).
Profit is \( S - C = 2C - C = C \).
The profit percentage is calculated as: \(\frac{C}{C}\times100\% = 100\%\).