Ответ:

Пошаговое объяснение:

a) 7/10 + 5/8 = 35/40 + 25/40 = 60/40 = 3/2 = 1ц. 1/2

б) 2 11/12 + 1 1/4 = 2 11/12 + 1 3/12 = 3ц. 14/12 = 3ц. 7/6 = 4ц. 1/6

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a) 7/12 - 3/8 = 14/24 - 9/24 = 5/24

б) 3 4/9 - 1 2/3 = 3 4/9 - 1 6/9 = 1ц. 7/9

2)

a)

b)

3)

a)

b)