Question

An article is sold at a profit of 10%.Had it been sold for Rs.20 more,12% profit would have been made.Find the cost price of the article.
Plz plz fast.

Answer 1

Say the cost price is $C$

$20$ equals the difference in profits : $2\% \text{~of~} C$
$20=0.02C\\2000=2C\\1000=C$

Answer 2

10% profit  =>    SP =  110/100 * CP
             or        SP =   1.10 CP

SP + Rs 20  gives  12% profit
   SP + Rs 20 =  112/100 *CP  or  1.12 CP
   1.10 CP + 20 =  1.12 CP

   0.02 CP = Rs 20
       CP = Rs 1, 000.