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2 years ago, father age was nine times the son age but 3 years later it will be 5 times only. find the present ages of the father and son​

User Bigchao
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1 Answer

9 votes

Answer:

The Father is currently 47 and the Son is 7

Explanation:

Let F and S be the present ages of Father and Son, respectively.

We are told that (F-2) = 9(S-2) [2 years ago, father age was nine times the son age]

We also learn that (F+3) = 5(S+3) [3 years later it will be 5 times only]

Take the first expression and isolate one of the variables (S or F). I'll isolate F:

(F-2) = 9(S-2)

F = 9S - 16

Now use this in the second expression:

(F+3) = 5(S+3)

((9S-16)+3) = 5(S+3)

9S-13 = 5S+15

4S = 28

S = 7

Since F = 9S-16,

F = 9*(7)-16

F = 47

Father is 47 and Son is 7

CHECK:

Was the father 9 times the age of his son 2 years ago?

Father would have been 45 and son 5. Yes, 9*5 = 45

In 3 years will he be 5 times older than his son? Yes, Father would be 50 and son would be 10. 5*(10) = 50

User Habin
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