功課~數學[英文題目]

the sum of ben's age and his father is smaller than two times the difference of their by 16.

「Ben和他的爸爸的歲數總和」少於「他們的歲數相差的兩倍」16.

設Ben的歲數為x歲,他的爸爸為y歲

2(y-x)-(x+y)=16
2y-2x-x-y=16
y-3x=16


2010-07-22 02:43:44 補充：
竟然撞秒數...真係難得!

文法不對，估計係
"two times the difference of theirs by 16" 或
"two times the difference of their age by 16"
唔可以只睇呢句，要將成句分成
(the sum of ben's age and his father) is smaller than
(two times) (the difference of their) by 16.
即係，假設B和F代表兩人歲數
(the sum of ben's age and his father) 即係 (B+F)
小於
(two times)= 兩倍
(the difference of their) 即係 (F-B)
成句解做，『和』小過『差』x2 ，小過16
即係 2(F-B) - (B+F) = 16