Ответ:

471.

1) 3,7х + 3,5у + 1,6х + 4,8у = 5,3х + 8,3у

2) 4,5m + 1,9n + 3,3m + 4,3n = 7,8m + 6,2n

472.

а) 9/10 * 5/6 = 3/2 * 1/2 = 3/4

б) 6/25 * 20/21 = 6/5 * 4/21 = 24/105

в) 17/30 * 26/51 = 1/15 * 13/3 = 13/45

г) 40/7 * 14/5 = 8/1 * 2/1 = 16/1

д) 57/37 * 74/86 = 57/1 * 2/86 = 114/86

е) 81/115 * 46/81 = 1/115 * 46/1 = 115/46

ж) 3/16 * 4 = 12/16 = 3/4

з) 23 * 5/46 = 115/46

и) 5/13 * 39 = 195/13

к) 5 * 2 целых 1/15 = 10 целых 5/15 = 10 целых 1/3

л) 3 целых 3/5 * 1 целая 1/9 = 18/5 * 10/9 = 2/1 * 2/1 = 4/1

м) 4 целых 2/7 * 2 = 8 целых 4/7

н) 2 целых 14/15 * 6 целых 6/11 = 44/15 * 72/11 = 4/5 * 24/1 = 92/5

о) 2 целых 2/25 * 1 целая 9/16 = 52/25 * 25/16 = 52/1 * 1/16 = 52/16

п) 13/43 * 8 целых 7/26 = 13/43 * 215/26 = 1/1 * 5/2 = 5/2

473.

а) 2/5 * 1/2 = 1/5 * 1/2 = 1/10, 2/5 * 2/5 = 4/25, 2/5 * 2 целых 1/2 = 2/5 * 5/2 = 1, 2/5 * 1 целая 7/8 = 2/5 * 15/8 = 1/1 * 3/4 = 3/4, 2/5 * 15/16 = 1/1 * 3/8 = 3/8

б) 4/9 * 1/4 = 1/9 * 1/1 = 1/9, 4/9 * 4/9 = 16/81, 4/9 * 4 целых 1/2 = 4/9 * 9/2 = 2/1 * 1/1 = 2/1

474.

3/4 ч = 45/60, 45 * 1/12 = 45/12 = 3 целых 9/12 = 3 целых 1/3 м

3/5 ч = 36/60, 36 * 1/12 = 36/12 = 3 м

5/6 ч = 50/60, 50 * 1/12 = 50/12 = 4 целых 2/12 м