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1) 14/24 - 15/40 = 7/12 - 3/8 =

ОЗ:

12/2

6/2

3/3

8/2

4/2

2/2

12*2=24

24/12=2

24/8=3

7*2/24 - 3*3/24 = (14-9)/24 = 5/24

2) 12/18 - 5/60 = 2/3 - 5/60

ОЗ: 60

2*20/60 - 5/60 = 40-5/60 = 35/60 = 7/12

3) 4/24 + 3/36 = 1/6 + 1/12

ОЗ 12

1*2/12 + 1/12 = 3/12 = 1/4 = 0,25