SOLUTION: A boy is 8 years older than his sister.How old is his sister when he is 3 times older than her.
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Question 992455: A boy is 8 years older than his sister.How old is his sister when he is 3 times older than her.
Answer by satyareddy22(84) (Show Source): You can put this solution on YOUR website!
Let the age of boy be x and his sister be y
A boy is 8 years older than his sister
=>x-y=8-----(1)
Boy is 3 times older than her
=>x=3y
Now substituting x=3y in (1)
3y-y=8
2y=8
y=8/2=4
x=3y=3*4=12
So the ages of boy and his sister are 12yrs and 4yrs respectively
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