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3 years ago a father was 3 times as old as his son in 5 years time he will be twice as old as his son in, what will be the sum of their years in four years time ​

 Jan 26, 2020
 #1
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+3

f -3   = 3 ( s -3)

 

f+5 = 2 (s+5)

 

 

 

 

f-3 = 3s-9    and

f+5 = 2s+10     or    -f-5 = -2s-10    add this to the first equation

 

-8 = s -19

s = 11                       f -3 = 3(s-3)    

                                f = 3(11-3)  + 3  = 27

 

11+4      +    27 + 4 = 46 years total in 4 years time

 Jan 26, 2020

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