哈哈爸 2009-4-19 09:53
求助数学题
Teams X and Y work separately on two different projects.
On sunny days, team X can complete the work in 12 days
while team Y needs 15 days.
On rainy days, team X’s efficiency decreases by 50%
while team Y’s efficiency decreases by 25%.
Given that the two teams started and ended the projects at the same time,
how many rainy days are there?.
阿弥陀佛 2009-4-20 22:51
回复 3#哈哈爸 的帖子
设:晴天x天,雨天y天,两人总工程量分别为A,B。
1/12Ax+1/12A*(1-50%)y=A
1/15Bx+1/15B*(1-25%)y=B
x=6,y=12.