1) 3 5/14 * 7/9 - 2 3/14 * 7/9 2) 7 1/5 * 2 1/8+7 1/5 * 1/58 3) 3/4 * 1 3/5+1 3/5 * 1 3/8 - 1 1/2 * 1 3/5 4) 3 9/14 * 0,3 - 0,3 * 1 10/21+0,3 * 1 1/6

1) 7/9* (3 5/14 - 2 3/14) = 7/9 * 1 2/14 = 7/9 * 1 1/7 = 7/9 * 8/7   7 сокращаем = 8/9

2)  точно в задании 1/58 ?   а не 1/8?

3) выносим за скобки 1 3/5 * ( 3/4 + 11/8 + 3/2) = 8/5 * 6/8+11/8-12/8 = 8/5 * 5/8 =1

4) 0,3* ( 3 9/14 -1 10/21 + 1 1/6)= 3/10* (153/42- 62/42 - 49/42) = 3/10 * 140/42=

3/10 * 3 14/42= 3/10 * 3 1/3 = 3/10 * 10/3 = 1