Question

a person sold his watch for rs 24 and got a percentage of profit equal to the cost prise then what is the cost price?

Answer 1

Let the cost price be rupees x.

Given that he sold his watch for rupees 24 and got a profit = to its cost price.

$\frac{24-x}{x} * 100 = x$

 (24 - x) * 100 = x^2

2400 - 100x = x^2

x^2 + 100x = 2400

x^2 + 100x - 2400 = 0

x^2 - 20x + 120x - 2400 = 0

x(x - 20) + 120(x - 20) = 0

(x + 120)(x - 20) = 0

x = -120,x = 20.


Therefore the cost price of the watch = 20 rupees.


Hope this helps!