AJWILL wrote:A certain shopkeeper used to calculate his profit percentage on the selling price of the articles rather than on its cost price. What is the profit percentage of the shopkeeper when calculated on the cost price ?
(1) Profit percentage when calculated on selling price of the articles is 20 percent.
(2) The cost price of the article is $50
The key to doing this DS question is understanding that to find the profit percentage, we need SP/CP ratio. With that in mind, let's look at the options.
1. Profit percentage when calculated on selling price of the articles is 20 percent.
=> (SP-CP)/SP = 0.2
=> 1-CP/SP = 0.2
So we can find SP/CP. Sufficient.
(2) The cost price of the article is $50.
This doesn't tell us about the CP/SP ratio. Insufficient.
A is the correct answer.
In case any of you are bemused by the explanation, here's the thing (though not required) in detail. We need to find (SP-CP)/CP = SP/CP - 1.
(SP-CP)/SP = 0.2
=> 1-CP/SP =0.2
=> CP/SP = 1-0.2 = 0.8
=> SP/CP = 1/0.8 = 1.25
=> SP/CP - 1 = 1.25 - 1 = 0.25 or 25%. Hence we have found the answer. So statement 1 is sufficient.
