Question

Rahul purchased an old water tank Rs. 7620 and spent Rs. 320 preparing its lid. After sometime he sold it for Rs. 9600. Find his profit or loss in percentage?

Answer 1

Hint: We start solving the problem by finding the total cost incurred to Rahul for purchasing the old water tank and for preparing the lid. We then find the selling price of the tank using the given information in the problem. We then find the profit for selling the tank by subtracting the cost price from the selling price. We then find the profit percentage using the formula $profit\%=\dfrac{\text{profit}}{\text{cost price}}\times 100$.

Complete step by step answer:
According to the problem, we are given that Rahul purchased an old water tank Rs. 7620 and spent Rs. 320 preparing its lid and sold it for Rs. 9600 after sometime. We need to find his profit or loss percentage.
Let us first find the cost incurred for Rahul for buying and for preparing the lid. Let us assume it as ‘c’.
So, we get $c=Rs.\left( 7620+320 \right)=Rs.7940$ ---(1).
According to the problem, we are given that Rahul sold this tanker for Rs. 9600 which means our selling price (s) as $s=Rs.9600$ ---(2).
Let us find the difference between selling price and cost price using the values obtained from equation (1) and (2).
So, we get $s-c=Rs.\left( 9600-7940 \right)=Rs.1660$ ---(3).
We can see that the difference between selling price and cost price is positive which means that Rahul attained profit.
So, the profit incurred by Rahul is Rs. 1660.
Now, we need to find the profit percentage. We know that profit percentage is defined as $profit\%=\dfrac{\text{profit}}{\text{cost price}}\times 100$.
So, let us substitute the values obtained from (1) and (3).
$\Rightarrow profit\%=\dfrac{1660}{7940}\times 100$.
$\Rightarrow profit\%=0.2091\times 100$.
$\Rightarrow profit\%=20.91\%$.

∴ We have found the profit percentage as 20.91%.

Note: We should not take the cost price as Rs. 7620 as the cost price for calculating the profit and profit percentage as it is not the total cost incurred to Rahul. We should know if the difference between the selling price and cost price is negative, then Rahul would have incurred loss and if it is zero, then there is neither loss nor profit. We should not divide profit with selling price with cost price while finding the profit percentage which is the most common mistake done by students.