Question

Imran gives 1% of his monthly income to his two sons as pocket money. The elder son gets 80% of the total amount given and he spends 80% of his share. If he saves Rs 60 per month, determine Imran ' s monthly income.

Answer 1

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Step-by-step explanation:

$Let \: total \: income \: be \: x$

$Pocket \: money \\ = \frac{1}{100} x$

$elder \: son \: share = \frac{1}{100} x \times \frac{80}{100} = \frac{1}{125} x$

$money \: elder \: son \: spend \: = 80\%$

$percentage \: of \: money \: that \: elder \: son \: save \: = 100\% - 80\% = 20\%$

$money \: save \: by \: son = \frac{1}{125} x \times \frac{20}{100} = \frac{1}{625x}$

According to question

$\: \: \: \: \: \: \: \: \: \: \: \: \: \frac{1}{625x} = 60$

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: x = 60 \times 625$

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: x = 37500$

Imran's monthly income is Rs. 37500