Question 271006
T = Tim's age
S = Son's age
T = 2S  :: Tim is twice as old as his son now.
T+6 = Tim's age in 6 years
S-6 = Son's age 6 years ago
T+6 = 3(S-6)  :: In six years, Tim's age will be three times what his son's was 6 years ago.
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T = 2S
T + 6 = 3(S-6)
Substitute 2S for T
2S + 6 = 3S - 18
Subtract 2S from both sides
6 = S - 18
Add 18 to both sides
24 = S
S = 24
Son's age is 24.
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Checking...
T = 2S, means Tim's age is 2(24) = 48
Six years ago, Son's age was 24-6 = 18
3 * 18 = 54
In six years, how will Tim be?
48+6 = 54
54 = 54
So, our solution checks.
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Answer:  Tim's son's age is 24 now.