Question

A person sold an electronic watch at Rs. 96 in such a way that his percentage profit is same as the cost price of the watch. If he sells it at twice the percentage profit of its previous percentage profit then the new selling price will be:

Answer 1

Suppose cost price of watch = xx
Then, profit percentage = x%x%
Selling price =x(100+x)100=x(100+x)100

Given that selling price is Rs.96. Therefore,
x(100+x)100=96100x+x2=9600x2+100x−9600=0(x+160)(x−60)=0x=60(taking +ve value))x(100+x)100=96100x+x2=9600x2+100x−9600=0(x+160)(x−60)=0x=60(taking +ve value))

i.e., cost price = Rs.60
profit percentage = 60%

If he sells it at twice the percentage profit, i.e., at 120%,
new selling price 
=60×(100+120)100=60×220100=60×(100+120)100=60×220100
= 6 × 22 = 132
Ans=₹132

Hope Its Helpful...