6 7/8-3 1/3+ 5 5/16
1)6 7/8-3 1/3= 6 21/24-3 8/24=3 13/24
2)3 13/24+ 5 5/16= 3 26/48+ 5 15/48=8 41/48
Ответ:8 41/48
Вроде так
12 дм 8 см * 9 = 128 см * 9 = 1152 см 115 дм 2 см периметр
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1) 75 + 82 = 157 км/ч скорость сближения
2) 157 * 4 = 628 км между городами
1/2 = 1*3 / 2*3 = 3/6 = 2/6 + 1/6 = 1/3 + 1/6
1/4 = 1*5 / 4*5 = 5/20 = 4/20 + 1/20 = 1/5 + 1/20
1/6 = 1*7 / 6*7 = 7/42 = 6/42 + 1/42 = 1/7 + 1/42
1/8 = 1*9 / 8*9 = 9/72 = 8/72 + 1/72 = 1/9 + 1/72
1. c + 15 = 69 + 28,
2. b - 19 = 16 + 14,
Решение:
1. c + 15 = 69 + 28,
c + 15 = 97,
c = 97 - 15,
c = 82.
2. b - 19 = 16 + 14,
b - 19 = 30,
b = 30 + 19,
b = 49.
Ответ: 1) 82, 2) 49.