Trắc nghiệm:
`1.C`
`10/16=(10xx2)/(16xx2)=20/32`
`2.B`
`2/5+5/7=(2xx7)/(5xx7)+(5xx5)/(5xx7)=14/35+25/35=39/35`
`3.D`
`39/12-3=39/12-3/1=39/12-(3xx12)/(1xx12)=39/12-36/12=3/12=1/4`
`4.A`
`2/4xx7/8=(2xx7)/(4xx8)=14/32`
Tự luận:
`16dam 32cm= 1632 cm`
`7km4m=7004m`
`4675m=4km675m`
`39056mm=39m 56mm.`