compare the following ratios
a)1:5 and 3:17
b)11:9 and 3:5

a) 1:5 = 1/5 and 3 :17 = 3/17 

1/5= 17/85

3/17 = 15/ 85

As 17/85 is bigger than 15/85 so 1:5 is bigger than 3:17

b) 11:9 = 11/9

3:5 = 3/5

11/9 = 55/45

3/5 = 27/45

So 11:9 is bigger than 3: 5