a)1 + 4 + 5 + 9 + 14 + … + 60 + 97 b)78 . 31 + 78 . 24 + 78 . 17 + 22.72 11/07/2021 Bởi Serenity a)1 + 4 + 5 + 9 + 14 + … + 60 + 97 b)78 . 31 + 78 . 24 + 78 . 17 + 22.72
Giải thích các bước giải: `a)1 + 4 + 5 + 9 + 14 + … + 60 + 97` `= 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97` `= 5 + 5 + 23 + 23 + 97 + 97` `= 2 (5 + 23 + 97)` `= 2.125` `= 250` `b)78 . 31 + 78 . 24 + 78 . 17 + 22.72` `=78.(31+24+17)+22.72` `=78.72+22.72` `=(78+22).72` `=100.72` `=7200` Bình luận
`a)1 + 4 + 5 + 9 + 14 + … + 60 + 97` `= 1+4+5+9+14+23+37+60+97` `=(1+4)+5+(9+14)+23+(37+60)+97` `=5+5+23+23+97+97` `=2.(5+23+97)` `=2.125` `=250` . `b)78 . 31 + 78 . 24 + 78 . 17 + 22.72` `=78.(31+24+17)+22.72` `=78.72+22.72` `=72.(78+22)` `=72.100` `=7200` . _Kim Rabit Lunar_ Bình luận
Giải thích các bước giải:
`a)1 + 4 + 5 + 9 + 14 + … + 60 + 97`
`= 1 + 4 + 5 + 9 + 14 + 23 + 37 + 60 + 97`
`= 5 + 5 + 23 + 23 + 97 + 97`
`= 2 (5 + 23 + 97)`
`= 2.125`
`= 250`
`b)78 . 31 + 78 . 24 + 78 . 17 + 22.72`
`=78.(31+24+17)+22.72`
`=78.72+22.72`
`=(78+22).72`
`=100.72`
`=7200`
`a)1 + 4 + 5 + 9 + 14 + … + 60 + 97`
`= 1+4+5+9+14+23+37+60+97`
`=(1+4)+5+(9+14)+23+(37+60)+97`
`=5+5+23+23+97+97`
`=2.(5+23+97)`
`=2.125`
`=250`
.
`b)78 . 31 + 78 . 24 + 78 . 17 + 22.72`
`=78.(31+24+17)+22.72`
`=78.72+22.72`
`=72.(78+22)`
`=72.100`
`=7200`
.
_Kim Rabit Lunar_