Question

Найти значения выражений: (1/9+1/3):2/3; 12x(2/3-1/4); 3/4:12-1/32; 1 1/5:2/3+1/3.

Answer 1

(1/9 + 1/3) : 2/3 = 2/3

1) 1/9 + 1/3 = 1/9 + 3/9 = 4/9

2) 4/9 : 2/3 = 4/9 · 3/2 = (2·1)/(3·1) = 2/3

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12 · (2/3 - 1/4) = 5

1) 2/3 - 1/4 = 8/12 - 3/12 = 5/12

2) 12 · 5/12 = 1 · 5 = 5

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3/4 : 12 - 1/32 = 1/32

1) 3/4 : 12 = 3/4 · 1/12 = (1·1)/(4·4) = 1/16

2) 1/16 - 1/32 = 2/32 - 1/32 = 1/32

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1 1/5 : 2/3 + 1/3 = 2 целых 2/15

1) 1 1/5 : 2/3 = 6/5 : 2/3 = 6/5 · 3/2 = (3·3)/(5·1) = 9/5 = 1 4/5

2) 1 4/5 + 1/3 = 1 12/15 + 5/15 = 1 17/15 = 2 2/15