Ответ:

1) y/4 = 95/19

y/4 = 5

y = 20

2) k : 17 = 35 : 170

170k = 595

k = 7/2 = 3,5

3)  115/20 = 23/m

115/20 = 23/m  m≠0

23/4 = 23/m

23m = 92

m = 4

4) 11 : c = 121 : 77

11 : c = 121 : 77  c≠0

121c = 847

c = 7