Question 370931: jack is 4 years older than twice his sister's age.in 4 years time he will be 11 years older than her. how old is joseph now? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! jack is 4 years older than twice his sister's age.
in 4 years time he will be 11 years older than her.
how old is joseph now?
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Equations:
j = 2s+4
(j+4) = (s+4)+11
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Substitute for "j" and solve for "s":
(2s+4+4) = s+15
2s + 8 = s+15
s = 7 yrs (Sister's age now)
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Since j = 2s+4, j = 16+4 = 20 yrs (Jack's age now)
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Cheers,
Stan H.
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