Question 974777
T = Tom's Age 
A = Amy's Age
B = Ben's Age

1)T=2A
2)A=1+B
3)T=3B

Substitute 2 into 1 
4) T= 2(1+B)
T= 2+2B
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Substitute 4 into 3 
3B = 2+2B

B = 2
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T=3(2)
=6
-----------------
6=2A
Therefore A=3
Amy = 3 years old.