a) \({\rm{}}1,5:2,16 = 150:216 = 25:36\)
b) \(\displaystyle 4{2 \over 7}:{3 \over 5} = {{30} \over 7}.{5 \over 3} = {{50} \over 7}\)
c) \(\displaystyle {2 \over 9}:0,31 = {2 \over 9}:{{31} \over {100}} = {2 \over 9}.{{100} \over {31}} \)\(\,\displaystyle = {{200} \over {279}}\)
