tính
a, 2/3 + 1/6 -1/2 b, 1/4 + 2/3 nhân 3/4 c,1/6 nhân 2/3 :2/9
d,7/8 -5/12 :5/6 e, 1/2 nhân 2/3 nhân 3/5 f,1/2: 2/3 : 3/5
tính a, 2/3 + 1/6 -1/2 b, 1/4 + 2/3 nhân 3/4 c,1/6 nhân 2/3 :2/9 d,7/8 -5/12 :5/6
By Mackenzie
`text{Đáp án :}`
`text{a)}` `2/3` + `1/6` – `1/2` = `12/18` + `3/18` – `9/18` = `15/18` – `9/18` = `6/18` = `1/3`
`text{b)}` `1/4` + `2/3` x `3/4` = `1/4` + `1/2` = `1/4` + `2/4` = `3/4`
`text{c)}` `1/6` x `2/3` : `2/9` = `2/18` : `2/9` = `2/18` x `9/2` = `18/36` = `1/2`
`text{d)}` `7/8` – `5/12` : `5/6` = `7/8` – `5/12` x `6/5` = `7/8` – `30/60` = `7/8` – `3/6` = `42/48` – `24/48` = `18/48` = `3/8`
`text{e)}` `1/2` x `2/3` x `3/5` = `2/6` x `3/5` = `6/30` = `1/5`
`text{f)}` `1/2` : `2/3` : `3/5` = `1/2` x `3/2` x `5/3` = `3/4` x `5/3` = `15/12` = `5/4`
Đáp án:
Giải thích các bước giải:
a) 2/3 + 1/6 -1/2=4/6+1/6-3/6
=5/6-3/6
=1/3
b, 1/4 + 2/3 x 3/4
=1/4+ 1/2
=1/4 +2/4
= 3/4
c,1/6 x 2/3 :2/9
=1/9:2/9
=1/9×9/2
=1/2
d,7/8 -5/12 :5/6
=7/8-1/2
=7/8-4/8
=3/8
e, 1/2 x 2/3 x 3/5
=1/3 x3/5
=1/5
f,1/2: 2/3 : 3/5
=3/4 x 5/3
=5/4