(1)
1) 8 7/60 - 3 3/4 = 8 7/60 - 3 45/60 = 4 22/60 = 4 11/30
2) 4 11/30 + 8 7/15 = 4 11/30 + 8 14/30 = 12 25/30
3) 15 2/5 - 12 25/30 = 15 12/30 - 12 25/30 = 2 17/30
ответ: 2 17/30
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(2)
1) 17 3/4 - 17 = 3/4
2) 2 1/2 - 17/24 = 2 12/24 - 17/24 = 1 19/24
3) 3/4 + 1 19/24 = 18/24 + 1 19/24 = 1 37/24 = 2 13/24
ответ: 2 13/24