Решить дроби: 1/2+1/3 1/4+2/5 2/3+1/4 3/4+2/5 5/7-1/6 3/4-1/3 1/8+1/4 2/3-5/9 1/2-5/12 5/12-2/9

Чтобы выполнить действия приведем дроби к общему знаменателю, а потом прибавим или отнимим значения в числителе:

1) 1/2 + 1/3 = 3/6 + 2/6 = (3 + 2)/6 = 5/6;

2) 1/4 + 2/5 = 5/20 + (2 * 4)/20 = (5 + 8)/20 = 13/20;

3) 2/3 + 1/4 = (2 * 4)/12 + 3/12 = (8 + 3)/12 = 11/12;

4) 3/4 + 2/5 = (3 * 5)/20 + (2 * 4)/20 = (15 + 8)/20 = 23/20 = 1 3/20;

5) 5/7 - 1/6 = (5 * 6)/42 - 7/42 = (30 - 7)/42 = 23/42;

6) 3/4 - 1/3 = (3 * 3)/12 - 4/12 = (9 - 4)/12 = 5/12;

7) 1/8 + 1/4 = 1/8 + 2/8 = (1 + 2)/8 = 3/8;

8) 2/3 - 5/9 = (2 * 3)/9 - 5/9 = (6 - 5)/9 = 1/9;

9) 1/2 - 5/12 = 6/12 - 5/12 = (6 - 5)/12 = 1/12;

10) 5/12 - 2/9 = (5 * 3)/36 - (2 * 4)/36 = (15 - 8)/36 = 7/36.