Question 531715: If Mavis is 5 yrs older than her brother. 5 years ago she was twice her brother's age, how old are they now? Found 2 solutions by oberobic, stanbon:Answer by oberobic(2304) (Show Source):
You can put this solution on YOUR website! M = Mavis' age
B = Brother's age
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M = B+5
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Five years ago...
M-5
B-5
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Mavis was twice her brother's age.
(M-5) = 2(B-5)
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Substitute M = B+5
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(B+5-5) = 2B-10
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B = 2B-10
-B = -10
B = 10
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M = B+5 = 15
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Check their ages 5 years ago.
B = 10-5 = 5
M = 15-5 = 10
M = 2*B
Correct.
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Answer: Mavis is 15 and her brother is 10 years old.
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Done.
You can put this solution on YOUR website! If Mavis is 5 yrs older than her brother. 5 years ago she was twice her brother's age, how old are they now?
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Equations:
m = b + 5
m-5 = 2(b-5)
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Substitute for "m" and solve for "b":
b+5-5 = 2b - 10
brother = 10 yrs (Brother's age now)
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Solve for "m":
m = b + 5
m = 10+5 = 15 yrs (Mavis's age now)
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Cheers,
Stan H.
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