Question
Fred said,"Each of my sons has twice as many sisters as he has brothers and each daughter has the same number of brothers as she has sisters."
How many sons and daughters does Fred have?
3 sons 4 daughters
How many sons and daughters does Fred have?
3 sons 4 daughters
Answers
Renkun
设x为姐妹,y为兄弟
x=y
x=2y
-x=1=y
-2=x=2y=1
所以兄弟x为4,姐妹y为3
x=y
x=2y
-x=1=y
-2=x=2y=1
所以兄弟x为4,姐妹y为3