Приведите дроби к общему знаменателю и найдите разность 5/6 и 2/3,5/6 и7/12, 11/15 и 2/3,40/60 и 9/15 ,2/3 и 1/8,17/42

1) 5/6 - 2/3 = 5/6 - 2 * 2/6 = 5/6 - 4/6 = (5 - 4)/6 = 1/6;

2) 5/6 - 7/12 = 2 * 5/12 - 7/12 = 10/12 - 7/12 = (10 - 7)/12 = 3/12 = 1/4;

3) 11/15 - 2/3 = 11/15 - 2 * 5/15 = 11/15 - 10/15 = (11 - 10)/15 = 1/15;

4) 40/60 - 9/15 = 40/60 - 4 * 9/60 = 40/60 - 36/60 = (40 - 36)/60 = 4/60 = 1/15;

5) 2/3 - 1/8 = 8 * 2/24 - 3/24 = 16/24 - 3/24 = (16 - 3)/24 = 13/24;

6) 17/42 - 6/21 = 17/42 - 2 * 6/42 = 17/42 - 12/42 = (17 - 12)/42 = 5/42;

7) 2/8 - 4/24 = 3 * 2/24 - 4/24 = 6/24 - 4/24 = (6 - 4)/24 = 2/24 = 1/12;

8) 23/45 - 4/15 = 23/45 - 3 * 4/45 = (23 - 12)/45 = 11/45.