A shopkeeper claims to sell his article at a discount of 10%, but marks his articles by increasing the cost of each by 20%. His gain percentage is:

Question

Question

This question was previously asked in

SSC CGL 2022 Tier-I Official Paper (Held On : 08 Dec 2022 Shift 3)

Answer 1

Given:

Initial discount = 10%

Increased cost = 20%

Concept used:

Let the cost of the article is x.

10% of x \(={10x\over100}\)

Calculations:

Initial discount is \(10x\over100\)

Price after discount:

\(x-{10x\over100}={90x\over100}\)

Now the increased cost is

20% of \({90x\over100}={1800x\over10000}\)

Price after increment is

\({90x\over100}+{1800x\over10000}={10800\over10000}\)

Gain percentage:

=\({{10800x\over10000}-x\over x}\)×100

=\({10800x-10000x\over10000x}\)×100

=\(80000\over10000\)

= 8%

Therefore, his gain percentage is '8%'.

Shortcut Trick

The shopkeeper sells at 10% discount, then MP : SP = 10 : 9

The shopkeeper mark-up 20% above cp, then CP : MP = 5 : 6

Now, we make equal unit of MP in both the ratio, we get ⇒ CP : SP : MP = 25 : 27 : 30

Then, gain% = 2/25 × 100 = 8%