Question 283256: A mother is twice as old as her daughter now, but 10 years ago, she was 3 times as
old as her daughter. Find their ages at present.
Found 3 solutions by mananth, ikleyn, josgarithmetic:
Answer by mananth(16949)   (Show Source):
You can put this solution on YOUR website! Let the daughter's age be x
mother's age will be 2x
Ten years ago
daughter's age x-10
Mother's age 3(x-10)
x-10 =3(x=10)
x=10=3x-30
3x-x=10+30
2x=40
x=40/2
x=20 Daughter's age now
Mother's age is 2x = 2*20 = 40 years
Answer by ikleyn(53742)  (Show Source):
You can put this solution on YOUR website! .
A mother is twice as old as her daughter now, but 10 years ago, she was 3 times as
old as her daughter. Find their ages at present.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In the post by @mananth, the setup equation is written incorrectly.
His manipulations that follow this incorrect equation, also have many errors,
although the final answer is correct.
His solution can not be considered as an etalon, so I came to bring a correct solution.
Let the daughter's age be x
mother's age will be 2x
Ten years ago
daughter's age x-10
Mother's age 2x-10
3(x-10) = 2x-10 <<<---=== This is a CORRECT setup equation
Simplify and find 'x'
3x-30 = 2x-10
3x-2x = 30-10
x = 20 Daughter's age now
Mother's age is 2x = 2*20 = 40 years
Solved correctly.
Answer by josgarithmetic(39791)  (Show Source):
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