In a festive season, a retailer sells readymade clothes at a discount of 20% and still gains 20% Of cost price. If the marked price for a pair of jeans is Rs4200. Find the retailer's cost price.

Given: In a festive season, a retailer sells readymade clothes at a discount of 20% and still gains 20% Of cost price.

Marked price of pair of jeans is Rs 4200

To do: Find retailers cost price.

Solution:

Marked price  =  4200

20% discount on the marked price, so the retailer sells clothes for 80% of the marked price.

Therefore Selling price =  80% of the marked price.

SP  = $\frac{ 80}{ 100} \times  4200$

       =  $80 \times 42$   

       =  3360

Selling price = 3360.

After selling the cloth for 3360, he gains 20% profit.

so, 120% of cost price = selling price

$\frac{120}{ 100} \times CP  =  SP$

$\frac{120}{ 100} \times CP = 3360$

                                             CP = $3360 \times \frac{100}{120}$

                                             CP = $\frac{336000}{120}$

                                             CP = 2800

Therefore, the Cost price   =  Rs2800