1) 5/6 - 2/3 = 5/6 - 4/6 = 1/6
2) 7/8 - 1/2 = 7/8 - 4/8 = 3/8
3) 1/6 * 3/8 = 1/16
4) 1/16 * (-4) = -1/4
ответ: -1/4
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1) 3/8 - 1/6 = 9/24 - 4/24 = 5/24
2) 2/9 - 2/5 = 10/45 - 18/45 = -8/45
3) 5/24 * (-8/45) = -1/27
4) -1/27 * 27 = -1
ответ: -1