Question

# Aman gave $40\%$ of the amount he had to Rohan. Rohan in turn gave one-fourth of what he received from Aman to Sahil. After paying Rs. $200$ to the taxi driver out of the amount he got from Rohan, Sahil now has Rs. $600$ left with him. How much will Aman have.(A) 4000 (B) 8000(C) 12000(D) Data inadequate

Hint: In this type of question we have to choose one person’s amount as variable “$X$” and rest are calculated by converting all in the form of variable $X$.

Let the amount with Aman be Rs. $X$, because we have to find how much money Aman will have.
Now according to the question Aman gave $40\%$ of the amount he had to Rohan.
Amount received by Rohan = $40\%$ of $X$
That is $\dfrac{{40 \times X}}{{100}}$
Now amount received by Sahil is $\dfrac{1}{4}$of Rohan’s amount
So total amount received by Sahil = $\dfrac{1}{4} \times \dfrac{{40 \times X}}{{100}}$
Total amount received by Sahil = $\dfrac{X}{{10}}$
Now the question says that after giving Rs.$200$ to the taxi driver Sahil have Rs.$600$as remaining amount
So $600 + 200 = \dfrac{X}{{10}}$
$800 = \dfrac{X}{{10}}$
By using cross-multiplication in above equation
From this we get $X = 8000$
And we choose $X$ as the amount of Aman, therefore we get an amount of Aman as Rs.$8000$.
Option B is the correct answer.

Note:This is the basic question of linear equations in one variable. Linear equations in one variable are always in the form of $ax + b = c$. In this type of question do not take more than one variable that creates a solution complicated.