Question

有红黄两种颜色的小球共140个，拿出红球的三分之一，再拿出10个黄球，剩下的红球和黄球正好一样多。原来红

球和黄球各多少个？

Answer 1

设红球x,黄球140-x
x(1-1/3)=140-x-10
5x/3=130
x=78
140-78=62个
答：红球78个，黄球62个。

Answer 2

设原来红球X个，黄球Y个，X+Y=140;2/3*X=Y-10;红球原来78个，黄球62个

Answer 3

解：设原来红球x个，黄球y个
x+y=140
2/3x=y-10

解之得x=78
y=62