The balance of a trader weighs 8% less than it should. Still the trader marks up his goods to get an overall profit of 20%. What is the mark up on the cost price?  Choose the correct choice from the following:  A) 40%  B) 8%  C) 10.4%  D) 16.66%  E) 9%
The most natural way to deal with 'weights' questions is by assuming values.   Say the trader's balance shows 100 gms. It is actually 92 gms because it weighs 8% less. Say, the cost price is $92 ($1/gm). Since he gets a profit of 20%, the selling price must be 92+(20/100)*92= 
<gadget id="calculator">92+(20/100)*92</gadget>
<output>552/5 = around 110.4</output>
$110.4   Since the cost price is actually supposed to be $100 (for 100 gms) and the selling price is $110.4, the mark up is simply 10.4%.   Ans : 10.4%
<result>C</result>
The balance of a trader weighs 8% less than it should. Still the trader marks up his goods to get an overall profit of 20%. What is the mark up on the cost price?