Question 656993
Serena is nine years old. Her mother is 39 years old. In how many years will her mother be three times as old as Serena?
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s = 9
m = 39
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Let the "number of years" asked for be "x".
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Equation:
39 + x = 3(9 + x)
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39 + x = 27 + 3x
2x = 12
x = 6 years
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Cheers,
Stan H.