Question

Вычислите, применяя распределительное свойство :
1) 1 2/5 × 2 5/7 - 1 2/5 × 3/14
2) 1/9 × 1 5/6 + 1 1/6 × 1/9
3) 1 3/8 × 3/5 - 3/5 + 1/8
Дам 20 баллов !срочно прошу

Answer 1

1  2/5 * 2  5/7 - 1  2/5 * 3 /14 = 1  2/5 * (2  5/7 - 3 /14) = 7/5 * (2  10/14 - 3 /14) =
7/5*(2  7/14) = 7/5 * 35/14 = 7/2 = 3  1/2
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1/9 * 1  5/6 + 1  1/6 * 1/9 = 1/9 * (1  5/6 + 1  1/6) = 1/9 * 3 = 3/9 = 1/3
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1  3/8 * 3/5 - 3/5 * 1/8 = 3/5 * (1  3/8 - 1/8) = 3/5 * 1  2/8 = 3/5 * 10/8 = 6/8 = 3/4 

Answer 2

а)1 2/5*(2 5/7 -3/14)=1 2/5*2 7/14=7/5*5/2=7/1*1/2=7/5=3 1/2