1.
1) 7 3/20 - 5 1/2 = 143/20 - 61/12 = (429-305)/60 = 124/60 = 31/15
2) 31/15 * 15/10 = 3,1
3) 6 3/7 * 1,4 = 45/7 * 14/10 = 9
4) 9:1,8 = 5
5) 3,1:5 = 0,62
Ответ: 0,62
2.
1) 5,7:0,3 = 19
2) 19 - 8 1/3 = 19/1 - 25/3 = (57-25)/3 = 32/3
3) 32/3 * 0,75 = 32/3 * 75/100 = 32/3 * 3/4 = 8
4) 2 1/8 + 1,75 = 17/8 + 175/100 = 17/8 + 7/4 = (17+14)/8 = 31/8 = 3,875
5) 3,875:15,5 = 0,25
6) 8:0,25 = 32
Ответ: 32