№ 1. 9 : 6 1/4 * 2 1/2 : 3/5 = 6
1) 9 : 6 1/4 = 9 : 25/4 = 9 * 4/25 = 36/25
2) 36/25 : 2 1/2 = 36/25 * 5/2 = (18*1)/(5*1) = 18/5
3) 18/5 : 3/5 = 18/5 * 5/3 = 18/3 = 6
№ 2. 1 5/6 : 2 1/3 * 3 3/4 * 4 1/5 = 43 целых 5/16
1) 1 5/6 : 2 1/3 = 11/6 : 7/3 = 11/6 * 3/7 = (11*1)/(2*7) = 11/14
2) 11/4 * 3 3/4 = 11/4 * 15/4 = 165/16
3) 165/16 * 4 1/5 = 165/16 * 21/5 = (33*21)/(16*1) = 693/16 = 43 5/16