`2/4 xx 3/5 =`
`(2 xx 3)/(4 xx 5) = ` `6/20`
`6/9 xx 7/8=`
`(6 xx 7)/(9 xx 8)` `= 42/72`
`5/15 xx 7/11=`
`(5 xx 7)/(15 xx 11)` `=1/3`
`12/14 xx 5/9 =`
`(12 xx 5)/(14 xx 9)` `= 60/126`
`2/4 -: 3/5 =`
`2/4 xx 5/3` `= 10/12`
`6/9 -: 7/8 =`
`(16 -: 4)/(36 -: 4)` `= 4/9`
`5/15 -: 7/11 =`
`5/15 xx 11/7` `= 55/105`
`5/9 -: 12/14 =`
`5/9 xx 14/12` `= 70/108`