Подскажите ! 2/3-3/5 5/6-1/4 7/9*2/5 14/15*10/49 4/15: 2/5

2/3 - 3/5 = 10/15 - 9/15 = 1/15
5/6 - 1/4 = 10/12 - 3/12 = 7/12
7/9 * 2/5 = 14/45
14/15 * 10/49 = (2*2)/(3*7) = 4/21
4/15 : 2/5 = 4/15 * 5/2 = (2*1)/(3*1) = 2/3

1)=7/12
2)=14/45
3)=4/21
4)=2/3