Ai làm được mình cảm ơn

`a)`

`@` `1/4=0,25`

`@` `7/4=1,75`

`@` `21/25=0,84`

`@` `16/25=0,64`

`@` `3/20=0,15`

`@` `5/20=1/4=0,25`

`@` `16/50=8/25=0,32`

`@` `45/50=9/10=0,9`

`@` `4/8=1/2=0,5`

`@` `5/8=0,625`

`@` `10/125=2/25=0,08`

`@` `18/125=0,144`

`----------`

`b)`

`@` `54/200=27/100=0,27`

`@` `98/200=49/100=0,49`

`@` `340/200=17/10=1,7`

`@` `68/200=17/50=0,34`

`@` `16/400=1/25=0,04`

`@` `32/400=2/25=0,08`

`@` `20/400=1/20=0,05`

`@` `120/400=3/10=0,3`

`@` `18/900=1/50=0,02`

`@` `72/900=2/25=0,08`

`@` `720/900=4/5=0,8`

`@` `1800/900=2`

`@` `64/80=4/5=0,8`

`@` `36/60=3/5=0,6`

`@` `63/70=9/10=0,9`

`@` `24/120=1/5=0,2`

`----------`

`c)`

`@` `3/6=1/2=0,5`

`@` `40/25=8/5=1,6`

`@` `16/32=1/2=0,5`

`@` `40/125=8/25=0,32`

`@` `18/36=1/2=0,5`

`@` `36/30=6/5=1,2`

`@` `48/32=3/2=1,5`

`@` `50/15=10/3=3,33`

`@` `150/60=5/2=2,5`

`------------`

`#Sanchy2008, hoidap247`