Question

28/45:63/40 ; 8/15:24 ; 8:4/5 ; 1: 7/19 ;

Answer 1

28/45 : 63/40=4/9*8/9=32/81
8/15:24=1/15:1/3=1/45
8:4/5=2*5=10
1:7/19= 19/7