Пошаговое объяснение:

№1

8/32 = (8:8)/(32:8) = 1/4

12/16 = (12:4)/(16:4) = 3/4

№2

5/8 и 3/4 => 5/8 и (3*2)/(4*2) => 5/8 и 6/8;

5/8 < 6/8, значит: 5/8 < 3/4

№3

5/8 = 5 : 8 = 0,625

2/15 = 2 : 15 = 0,1333... = 0,1(3)

№4

9/16 - 3/8 = 9/16 - 6/18 = 3/18 = 1/6

2 3/4 + 3 2/5 = 2 15/20 + 3 8/20 = 5 23/20 = 6 3/20

5 - 3 14/17 = 4 17/17 - 3 14/17 = 1 3/17