(60-40+3*5+40*(5/60))/(1-5/60)=(20+15+40*(1/12))/(1-1/12)=(35+40/12)/(11/12)=(35*12+40)/11=460/11=41又(9/11)分再过41又(9/11)分钟,时针和分针第一次重合.40+41又(9/11)-60=81又(9/11)分-60=21又(9/11)分即在4...