Question

A person purchases 20 litre of juice at Rs. 2.20 per litre and diluted it with water to make the contents 22 litres. In order to earn a 10% profit, he should sell the juice at
A. Rs. 2.20
B. Rs. 2.00
C. Rs. 2.35
D. Rs. 2.40

Answer 1

Hint: For the type of question first calculate the total amount person has paid to buy the total product, then add the amount he/she has increased through the addition of other mixtures, through which we will get the total product person would have to make a sell. Now to find the total amount of ‘x’ percent amount profit, we will give it by $\dfrac{x}{100}\times $ Total amount purchase. Now to further know the exact value of per product of all purchases we will give it by Total product after the addition of mixture divided by the total amount of ‘x’ percent amount profit.

Complete step by step solution:
 So the total amount person paid for the purchase of 20 Litre of juice is = amount of each litre $\times $ total Litre of juice person bought
$\begin{align}
  & =2.20\times 20 \\
 & =44Rs \\
\end{align}$
As the person had added some water to increase the amount of juice, as given in the question he made a total of 22 litres of juice together.
Now to make $10%$ a profit of the total amount he made to purchase is =$\dfrac{10}{100}\times 44=4.4$.
So total amount he should make after selling whole juice is$44+4.4=48.4Rs.$
To find out the exact amount for each litre of juice
$\text{cost of 1 litre of juice =}\dfrac{\text{total cost we want to generate}}{\text{total amount of juice we have}}$
So, we get
$\text{cost of 1 litre of juice =}\dfrac{48.4}{22}$
So, on further simplification, we will get
$\text{cost of 1 litre of juice =2}\text{.2}$
So the person should sell the juice at 2.2Rs per Litre in order to make a $10%$ profit.
Hence, the person can either sell whole juice at 48.4 Rs. Or can sell at 2.2 Rs per litre.

Note: As here we had simply done the calculation, we should only know the basics of calculating the percent. Here in this question we already got the final amount after mixture, as in general, we need to figure that out through the given information of adding different mixtures in the main solution/product. Which I had mentioned in the hint part.