Question 582180
the difference between Maria's age and her sister's age is 3. If Maria is seven years younger than twice her sister's age, how old is Maria?
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Equations:
m - s = 3
m = 2s-7
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Sustitute for "m" and solve for "s":
2s-7-s = 3
s = 10 yrs (sister/s age)
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Solve for "m":
m = 2s-7
m = 2*10-7
m = 13 yrs (Maria's age)
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Cheers,
Stan H.