5/11*4/15=

9/14*5/12=

18*2/9=

15*9/10=

3/7*21=

4/9*6=

15*2 ц3/5=

1 ц3/7*2 ц4/5=

5/11*4/15 = (5*4) / (11*15) = 4 / (11*3) = 4/33

9/14*5/12 = (9*5) / (14*12) = (3*5) / (14*4) = 15/56

18*2/9 = (18*2) / 9 = 2*2 = 4

15*9/10 = (15*9) / 10 = (3*9) / 2 = 27/2

3/7 * 21 = (3*21) / 7 = 3*3 = 9

4/9*6 = (4*6) / 9 = 4*2 = 8

Хз что за "ц"