Question

Выполните умножение (340-341):
1) 2 1/4•1 1/3
2)5 5/12•1 5/13
3)4 3/8•1 1/7
4)4 9/10•3 1/3

Answer 1

1) 2 целых 1/4 = (2·4+1)/4 = 9/4

1 целая 1/3 = (1·3+1)/3 = 4/3

2 1/4 · 1 1/3 = 9/4 · 4/3 = 9/3 = 3

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2) 5 целых 5/12 = (5·12+5)/12 = 65/12

1 целая 5/13 = (1·13+5)/13 = 18/13

5 5/12 · 1 5/13 = 65/12 · 18/13 = (5·3)/(2·1) = 15/2 = 7 целых 1/2

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3) 4 целых 3/8 = (4·8+3)/8 = 35/8

1 целая 1/7 = 7/7 + 1/7 = 8/7

4 3/8 · 1 1/7 = 35/8 · 8/7 = 35/7 = 5

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4) 4 целых 9/10 = (4·10+9)/10 = 49/10

3 целых 1/3 = (3·3+1)/3 = 10/3

4 9/10 · 3 1/3 = 49/10 · 10/3 = 49/3 = 16 целых 1/3