SOLUTION: A boy's age is three times the age of his sister. Their ages together total 16 years. What is the age of each?

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Question 14935: A boy's age is three times the age of his sister. Their ages together total 16 years. What is the age of each?
Answer by bam878s(77) About Me  (Show Source):
You can put this solution on YOUR website!
Let x = age of boy and y = age of girl.
Then x=3y and x+y=16.
plug x into second equation to get,
3y+y=16 or 4y=16.
Now, divide both sides by 4
y=4. The age of the girl is 4.
Now use this to solve for x.
x = 3y = 3(4).
so x = 12. The age of the boy is 12.