выполните действия а)9/56-(7/15-5/12)×(3/14+1/2) б)(2/3+7/8-5/6)×(1-5/17)​

Ответ: 1/8 и 1/2

Пошаговое объяснение:

а)

9/56 - (7/15 - 5/12) × (3/14 + 1/2) =

= 9/56 - (28/60 - 25/60) × (3/14 + 7/14) =

= 9/56 - (3/60) × (10/14) =

= 9/56 - 1/20 × 5/7 =

= 9/56 - 1/28 =

= 9/56 - 2/56 = 7/56 = 1/8

б)

(2/3 + 7/8 - 5/6) × (1 - 5/17) =

= (16/24 + 21/24 - 20/24) × (17/17 - 5/17) =

= 17/24 × 12/17 = 1/2 × 1/1 = 1/2