Bài `1:`
`a)` Số đối `: 5; -3/8; 0; -9/14`
`b)` Số nghịch đảo`: 12/-11; 1/-10; 3/5`
Bài `2:`
`b) 47/2; 7/3; 23/7; 5/3`
Bài `3:`
`a)`
`-6/3= -2`
`b)`
`10/5= 2`
`c)`
`= -16/36+ 15/36`
`= -1/36`
`d)`
`= -25/60- 21/60`
`=-23/30`
`e)`
`= -5/3`
`f)`
`= -7/22. 11/-14`
`= 1/4`
Bài `4:`
`a)`
`= 7/11.( -13/15+ 28/15)`
`= 7/11. 1`
`= 7/11`
`b)`
`= 1/15+ -2/3`
`= 1/15+ -10/15`
`= -9/15= -3/5`
`c)`
`5/12- 1/60
`= 25/60- 1/60`
`= 24/60= 2/5`
`d)`
`= 19/24. 24/38. 13/15`
`= 1/2. 13/15`
`= 13/30`
`e)`
`= 138/13-( 44/13- 2/5)`
`= ( 138/13- 44/13)- 2/5`
`= 94/13- 2/5`
`= ...`