SOLUTION: Dayna is 8 and her mother is 31. How long will it be before her mother is twice as old as she is?

Question 658387: Dayna is 8 and her mother is 31. How long will it be before her mother is twice as old as she is?

Found 2 solutions by stanbon, josmiceli:
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Dayna is 8 and her mother is 31. How long will it be before her mother is twice as old as she is?
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Equations:
d = 8
m = 31
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Let the "how long" be x:
m + x = 2(d+x)
31 + x = 2(8+x)
31 + x = 16 + 2x
x = 15 (# of years required)
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Dayna will be 8+15 = 23
Mother will be 31 + 15 = 46
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Cheers,
Stan H.

Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
Add years to both their ages
given:

In 15 years the Mother's age will be twice the Daughter's
check:
In 15 yrs Mother is 31 + 15 = 46
In 15 yrs Daughter is 8 + 15 = 23
46 is twice 23
OK
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