)^_^ 7,2: 2,7=32y/3 35: (21-5y)=5: 2 (16-x): 13 4/7=7/9: 10 5/9

7,2:2,7=32y/3

32y * 2,7 = 7,2 * 3

86,4y = 21,6

y = 21,6 : 86,4

y = 0,25

35:(21-5y)=5:2  

5 * (21 - 5y) = 35 * 2

105 - 25y = 70

25y = 105 - 70

25y = 35

y = 35 : 25

y = 1,4

(16-x):13 4/7=7/9:10 5/9

( 16 - x ) : 95/7 = 7/9 : 95/9

( 16 - x) : 95/7 = 7/9 * 9/95

( 16 - x) : 95/7 = 7/95

16 - x = 7/95 * 95/7

16 - x = 1

x = 16 - 1

x = 15