A shopkeeper sells his goods at cost price but uses a weight of 800 gm instead of kilogram weight. What is his profit percentage?
18%
40%
25%
20%
Explanation:
If a trader professes to sell his goods at cost price, but uses false weights, then
Gain% = $\left[\dfrac{error}{true value-error}\times100\right]\%$
So here profit percentage = $\left[\dfrac{200}{\left(1000 - 200\right)} \times 100\right]\%$
= $\left[\dfrac{200}{800}\times100\right]$= 25%