In sunny days, it takes 12 days for team a to complete the task, and 15 days for team B to complete the task. In rainy days, the work efficiency of team a will decrease by 50%, and that of team B will decrease by 25%. In the last two construction teams to start and complete the two projects at the same time, there will be more difficulties in rainy days_____ Day two One by one, one answer, two answers, two answers, three answers,

A does 1 / 12 work quantity every day, 1 / 24 when it rains; B does 1 / 15 every day, 1 / 20 when it rains
Make sunny X days, rainy y days
1 / 12x + 1 / 24y = 1 (project completion) → 2x + y = 24
1/15X+1/20Y=1→4X+3Y=60
X = 6, y = 12
So there are 12 rainy days

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