Первое выражение
15 4/9 - 4 4/9 * 3 3/8 = 4/9
1) 4 4/9 * 3 3/8 = (4 * 9 + 4)/9 * (3 * 8 + 3)/8 = 40/9 * 27/8 = 5 * 3 = 15
2) 15 4/9 - 15 = 4/9
Второе выражение
81/88 * (6 - 1 13/15 * 1 19/21) = 2,25
1) 1 13/15 * 1 19/21 = (1 * 15 + 13)/15 * (1 * 21 + 19)/21 = 28/15 * 40/21 =
= 32/9 = 3 5/9
2) 6 - 3 5/9 = 5 9/9 - 3 5/9 = 2 4/9
3) 81/88 * 2 4/9 = 81/88 * (2 * 9 + 4)/9 = 81/88 * 22/9 = 9/4 = 2,25
Третье выражение
(5 1/16 - 1 1/8) * (5/6 + 3/14) = 4,125
1) 5 1/16 - 1 1/8 = 4 17/16 - 1 2/16 = 3 15/16
2) 5/6 + 3/14 = 35/42 + 9/42 = 44/42 = 22/21
3) 3 15/16 * 22/21 = (3 * 16 + 15)/16 * 22/21 = 63/16 * 22/21 =
= 33/8 = 4 1/8 = 4,125
Четвёртое выражение
5 1/16 - 1 1/8 * (5/6 + 3/14) = 3 99/112
1) 5/6 + 3/14 = 35/42 + 9/42 = 44/42 = 22/21
2) 1 1/8 * 22/21 = (1 * 8 + 1)/8 * 22/21 = 9/8 * 22/21 = 33/28
3) 5 1/16 - 33/28 = (5 * 16 + 1)/16 - 33/28 = 81/16 - 33/28 =
= 567/112 - 132/112 = 435/112 = 3 99/112
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Пошаговое объяснение:
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