Question 4 the day : April 1, 2002
The question for the day is a sample practice problem in profit, loss, discounts, an Arithmetic Topic and the problem provides an understanding of the different terms such as Cost Price, List Price, Selling price and margins.

Question
A trader makes a profit equal to the selling price of 75 articles when he sold 100 of the articles. What % profit did he make in the transaction?

1. 33.33%
2. 75%
3. 300%
4. 150%

Correct Answer - 300% profit. Choice (3)

Explanatory Answer

Let S be the selling price of 1 article.
Therefore, the selling price of 100 articles = 100 S. --(1)

The profit earned by selling these 100 articles = selling price of 75 articles = 75 S -- (2)

We know that Selling Price (S.P.) = Cost Price (C.P) + Profit -- (3)
Selling price of 100 articles = 100 S and Profit = 75 S from (1) and (2). Substituting this in eqn (3), we get
100 S = C.P + 75 S. Hence, C.P = 100 S - 75 S = 25 S.
Profit % =

Typically, you should take about 25 to 30 seconds to crack a problem of this kind. In reality, you should not be writing down all the steps that I have used to explain the solution. You should probably be framing equation (3) directly and compute the last step. The rest of the steps should be done mentally as you read the question for the first time.

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