Question 510937
M = 3*J
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In 7 years, their ages will be:
M+7
J+7
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M+7 = 2*(J+7)
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Substitute M=3*J
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3J + 7 = 2J + 14
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J = 7
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M = 3J = 21
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Check their age relationship in 7 years.
M+7 = 28
J+7= 14
M+7 = 2(J+7)
Correct.
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Answer: Matthew is 21, and Jenny is 7.
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Done.