Представим в виде десятичной дроби. Для этого числитель делим на знаменатель.
1) 5/7 = 5 ÷ 7 = 0,7142857143;
2) -8/15 = -8 ÷ 15 = -0,5333333333;
3) 8/9 = 8 ÷ 9 = 0,8888888889;
4) -2/21 = -2 ÷ 21 = -0,0952380952;
5) 5/22 = 5 ÷ 22 = 0,2272727273;
6) 4/45 = 4 ÷ 45 = 0,0888888889;
7) 1 4/11 = (1 × 11 + 4)/11 = 15/11 = 15 ÷ 11 = 1,3636363636;
8) 2 1/16 = (2 × 16 + 1)/16 = 33/16 = 33 ÷ 16 = 2,0625;
9) -1 2/3 = -(1 × 3 + 2)/3 = -5/3 = -5 ÷ 3 = -1,6666;
10) -1 1/27 = -(1 × 27 + 1)/27 = -28/27 = -28 ÷ 27 = -1,037037037;
11) 5 2/3 = (5 × 3 + 2)/3 = 17/3 = 17 ÷ 3 = 5,6666;
12) 4 5/6 = (4 × 6 + 5)/6 = 29/6 = 29 ÷ 6 = 4,8333333333;
Пошаговое объяснение:
(2 1/2 + 1 1/3): (1/6 - 5 3/7) = -161/221
1) 2 1/2 + 1 1/3 = 2 3/6 + 1 2/6 = 3 5/6
2) 1/6 - 5 3/7 = -(5 3/7 - 1/6) = -(5 18/42 - 7/42) = -5 11/42
3) 3 5/6 : ( -5 11/42) = -(23/6 : 221/42) = -(23·42:(6·221)) = -(23·7:221) = -161/221