Cách `1`:
`75/100+3/4xx29+75%xx30+0,75xx40`
`=75/100+3/4xx29+75/100xx30+3/4xx40`
`=75/100+3/4xx29+75/100xx30+3/4xx40xx1`
`=75/100xx(29+30+40+1)`
`=75/100xx100`
`=7500/100=75`
Cách `2`:
`75/100+3/4xx29+75%xx30+0,75xx40`
`=75/100+3/4xx29+75/100xx30+3/4xx40`
`=3/4+3/4xx29+3/4xx30+3/4xx40`
`=3/4+3/4xx29+3/4xx30+3/4xx40xx1`
`=3/4xx(29+30+40+1)`
`=3/4xx100`
`=300/4=75/1=75`