2 câu trả lời
Đáp án:
`2016/2017xx2/3xx2017/2016xx3/2`$\\$ `= ( 2016/2017 xx 2017/2016) xx ( 2/3 xx 3/2)`$\\$ `=( \cancel{2016} xx\cancel{2017})/(\cancel{2017} xx \cancel{2016}) xx 6/6`$\\$ `= 1 xx 1`$\\$ `= 1`$\\$$\\$ `7/10 - x/20 = 2/5`$\\$ ` x/20 = 7/10 - 2/5`$\\$ `x/20 = 7/10 - 4/10`$\\$ `x/20 = 3/10`$\\$ `10xxx = 20xx3`$\\$ `10xxx = 60`$\\$ `x= 60 : 10`$\\$ `x= 6`$\\$ Vậy `x= 6`
`@ 2016/2017 xx 2/3 xx 2017/2016 xx 3/2`
`=(2016/2017 xx 2017/2016) xx (2/3 xx 3/2)`
`=1 xx 1`
`=1`
`@ 7/10 - x/20 = 2/5`
`14/20 - x/20 = 8/20`
`14-x=8`
`x= 14-8`
`x=6`