437 вычеслите: 1) 1/2 + 4/7 - 3/14 2) 1/5 - 2/15 + 1/30 3) 1/10 + 7/20 - 2/40 4) 17/20 - 3/10 - 11/60 5) 3/20 + 7/10 - 3/40 6) 9/40 + 3/4 - 19/20

1) 1/2 + 4/7 - 3/14 = 7+8-3/14= 6/7.

2) 1/5 - 2/15 + 1/30 = 6-4+1/30 = 1/10.

3) 1/10 + 7/20 - 2/40 = 1/10+6/20= 1+3/20= 2/5.

4)17/20 - 3/10 - 11/60 = 51-18-11/60= 11/30.

5) 3/20 + 7/10 - 3/40 = 6+28-3/40 = 31/40

6) 9/40 + 3/4 - 19/20 = 9+30-38/40 = 1/40.