Đáp án:
`45`
Giải thích các bước giải:
`9/17xx6/11xx5 2/3xx121xx5/22`
`=9/17xx6/11xx17/3xx121xx5/22`
`=9/17xx17/3xx6/11xx5/22xx121`
`=(9xx17)/(17xx3)xx(6xx5)/(11xx22)xx121`
`=9/3xx(3xx5)/(11xx11)xx121`
`=3xx15/121xx121`
`=3xx(15xx121)/121`
`=3xx15`
`=45`