Question

Out of a certain sum of a money a boy spends 3/5, and then 1/4 of the remainder. He has rs 15 left.how much amount had he at first

Answer 1

150 rs.
1/4of x =15
We fet x= 60
Therefore
x-3/5of x = 60

Taking LCM we get
5x-3x/5=60
2x=60*5
x=300/2
x=150
So he had 150 rs

Answer 2

$\large{\underline{\rm{\blue{\bf{Question:-}}}}}$

Out of a certain sum of a money a boy spends 3/5, and then 1/4 of the remainder. He has Rs. 15 left. How much amount had he at first?

$\large{\underline{\rm{\green{\bf{Given:-}}}}}$

Amount of money he spends = 3/5 of the total

Fraction of money left = 1/4 of the total

Amount left = Rs. 15

$\large{\underline{\rm{\green{\bf{To \: Find:-}}}}}$

The amount he had with him first.

$\large{\underline{\rm{\green{\bf{Solution:-}}}}}$

Let us consider x as the amount with him first.

He spends 3/5 of the total, then

Amount spent = $\sf \dfrac{3}{5} \: x$

Amount remaining with him = $\sf x-\dfrac{3}{5} \: x$

$\sf = \dfrac{2}{5} \: x$

Then, he spends 1/4th of remaining amount

Amount spent second time = $\sf \dfrac{1}{4} \times \dfrac{2}{5} \: x$

$\sf =\dfrac{1}{10}$

Now, the remaining amount,

Amount remaining with him = $\sf \dfrac{2}{5} \: x - \dfrac{1}{10} \: x$

$\sf =\dfrac{4}{10} \: x-\dfrac{1}{10} \: x$

$\sf =\dfrac{3}{10} \: x$

Given that, the remaining amount is Rs. 15

Amount with him,

$\sf \dfrac{3}{10} \: x=15$

$\longrightarrow \sf x=50$

Therefore, the amount with him in the start was Rs. 50