Question

a father gives 1%of his monthly income to his two sons as pocket money. the elder son gets 80%of the total amount of money given and he spends 80 %of his share.If hesaves 20 rupees per month, determine father's monthly income​

Answer 1

Let father's monthly income be x .

Now

Amount is given To his Sons

= 1 % of his salary = x × 1/100 = x/100

again, Amount is Received by elder Son = 80% of x/100 = 80/100 × x/100

= 80x/10000 = 8x/1000 = x/125

it is given that he spends 80% of his share

So Amount saved by elder son = 20%

so, amount saved by elder son = 20% of amount gained by elder son

= 20 /100 × x/125

= x/625

a/c to question, amount saved by elder son =20 rs.

or, x/625 = 20

or, x = Rs 12,500