Question 776351
Peter said "I am three times as old as my brother, but in 6 years time I will only be twice as old as him". If Peter's brother's age now is b years, how old is Peter in terms of b ? How old will they be in 6 years time? 
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Equations:
p = 3b
p+6 = 2(b+6)
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Substitute for "p" and solve for "b":
3b+6 = 2b + 12
b = 6 years (Brother's age now)
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how old is Peter in terms of b ? 
p = 3b = 18 years
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How old will they be in 6 years time?
Peter will be 24 yrs
Brother will be 12 yrs. 
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Cheers,
Stan H.
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