Question

If the cost price of $21$ cell phones is equal to selling price of $18$ cell phones, find the profit percent

Answer 1

Let the C.P. of each cell phone be $Re.1$. Then the C.P. of $21$ cell phones is $Rs.21$.
By the given data, S.P. of $18$ cell phones $=$ C.P, of $21$ cell phones $=Rs.21$.
Therefore, S.P. of $1$ cell phone is $Rs\frac{21}{18}$. This gives
$Profit=S.P.-C.P.=\frac{21}{18}-1=\frac{3}{18}=\frac{1}{6}$.
Thus, there is a profit of $Rs.1/6$ on each cell phone. Now we can calculate profit percentage:
Profit percentage $=\frac{profit}{C.P.}\times 100=\frac{1/6}{1}\times 100=\frac{50}{3}=16\frac{2}{3}$.
Therefore, the profit percentage is $16\frac{2}{3}$%.