SOLUTION: A son in the family says I have sisters twice as many as brothers. A daughter in the same family says I have brothers 2/3 as many as sisters. How many children are in the family?

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Question 1003113: A son in the family says I have sisters twice as many as brothers. A daughter in the same family says I have brothers 2/3 as many as sisters. How many children are in the family?
Answer by josgarithmetic(39616) About Me  (Show Source):
You can put this solution on YOUR website!
x, number of sisters
y, number of brothers

Each brother or sister excludes himself or herself in his or her counting of the other gendered siblings.
system%28x=2y-1%2Cy=%282%2F3%29x-1%29

The x equation is what the brother says; and the y equation is what the sister says.

Did this interpretation work?
system%28x=2y-1%2C3y=2x-3%29

3y=2%282y-1%29-3
3y=4y-2-3
3y=4y-5
3y%2B5=4y-5%2B5
3y%2B5=4y
3y%2B%28-3y%29%2B5=4y%2B%28-3y%29
highlight%285=y%29

Return to the system and take x=2y-1
x=2%2A5-1
x=10-1
highlight%28x=9%29

This family has 9 girls (the sisters) and 5 boys (the brothers).