Применяя распределительное свойство умножения, вынесите общий множитель за скобки. Вычислите: 2/5 *6/13 + 1/4* 6/13 , 5/8 *5/6 -1/4 *5/6, 3/5 -3/5 *2/7, 1/7 *1/8 + 1/7 * 1/6

Ответ учителя по предмету Математика

2/5×6/13+1/4×6/13 = 6/13(2/5+1/4) = 6/13(8/20+5/20) = 6/13×13/20 = 3×1/10 = 3×0,1 = 0,3

5/8×5/6-1/4×5/6 = 5/6(5/8-1/4) = 5/6(5/8-2/8) = 5/6×3/8 = 5/2×1/8 = 2,5×1/8= 0,3125

3/5-3/5×2/7 = 3/5-6/35 = 21/35-6/35 = 15/35= 3/7

1/7×1/8+1/7×1/6 = 1/7(1/8+1/6) = 1/7(6/48+8/48) = 1/7(14/48) = 1/7(7/24) = 1/7×7/24 = 1×1/24 = 1/24