You can put this solution on YOUR website! Let = A's age now
Let = B's age now = A's age 7 years ago = B's age 7 years ago
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given:
7 years ago, A was 3 years younger than B is now
(1)
7 years ago, B was twice as young as A ( half A's age )
(2)
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(2)
(2)
(2)
and
(1)
(1)
(1)
(1)
Substitute (1) into (2)
(2)
(2)
(2)
(2)
A is 15
check:
(1)
(1)
(1)
(2)
(2)
(2)
(2)
OK
