Question

a boy spends 3 by 4 of his pocket money and then 45 of remainder is given to her sister if he has rupees
40 left what did he have first ​

Answer 1

let pocket money be = x

X -3/4x is amount remaining with him after spending money.

X -3/4x= x/4 (on solving)

now he gave 4/5of remaining amount to his sister.

= x/4 - 4/5 of x/4

= x/4 - x/5

= x/20

amount remaining with him is =40

x/20=40

x=800

his pocket money is 800

Answer 2

Your answer mate

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let the total money be=x

the boy spend money=3/4*x=3x/4

remainder=x-3x/4=x/4

money given to the sister=x/4*4/5=x/5

the total money=x-(3x/4+x/5)=40

=x-(19/20)=40

x-800/19

x/1-800/19x

19x-800/19x=800 ans

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