Question

Решите быстро плз
313,317,319 первый столб

Answer 1

1/4+1/5=5/20+4/20=9/20
1/3+1/7=7/21+3/21=10/21
3/5+3/4=12/20+15/20=27/20=1,35

Answer 2

1/4 + 1/5 = 5/20 + 4/20 = 9/20

1/3 + 1/7 = 7/21 + 3/21 = 10/21

3/5 + 3/4 = 12/20 + 15/20 = 27/20