Today Frank's age = x and John's age = x+15

and after 5 years, john will be twice of Frank,

i.e. 2*(x+5)= (x+15+5)

solving this,

we get x = 10 , which is todays age of Frank.

Then after 4 years Frank will 10 + 4 = 14 years old

+1 vote

Frank is 15 year younger than John.In 5 years,John will be twice as old as Frank.How old Frank will be next four years?

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