Đáp án:
`a)` `7/3`
`b)` `20/3`
Giải thích các bước giải:
`5B :`
`a) 0,(6) + 1,(6)`
= `6/9` `+ 1 + 0,(6)`
= `2/3` + `3/3` + `2/3`
= `7/3`
Vậy `0,(6) + 1,(6)` = `7/3`
`b) 3,(6) + 1,(36) .` 2`1/5`
`= 3 + 0,(6) + 1 + 0,(36) .` `11/5`
`= 3 +` `6/9` `+ 1 +` `36/99` `.` `11/5`
`= 3 +` `2/3` `+` (1 + `4/11` ) . `11/5`
`=` `9/3` + `2/3` + `15/11` . `11/5`
`=` `11/3` `+ 3`
`=` `11/3` + `9/3` = `20/3`
Vậy `3,(6) + 1,(36) .` 2`1/5` = `20/3`
