Câu 1
`121/27` × `54/11` < n < `100/21` : `25/126`
`121/27` × `54/11` < n < `100/21 × `126/25`
`6534/279` < n < `12600/525`
22 < n < 24
=> n = 23
Câu 2
B = `1/7` × 3`1/11` - `1/7` × `9/11` - `1/7`
B = `1/7` × `34/11` - `1/7` × `9/11` - `1/7` × `11/11`
B = `1/7` × ( `34/11` - `9/11` - `11/11` )
B = `1/7` × `14/11`
B = `14/77` = `2/11`
Câu 3
2011 × 2012 × 2000 × ( `5/6` - `1/3` - 50% ) × 2013 + 10
Ta thấy : `5/6` - `1/3` - 50%
= `5/6` - `1/3` - `1/2`
= `5/6` - `2/6` - `3/6`
= 0
Vì `5/6` - `1/3` - 50% = 0 nên 2011 × 2012 × 2000 x ( `5/6` - `1/3` - 50 ) = 0
0 + 10 = 10
=> Giá trị biểu thức bằng 10
`#cactus`