题目内容
计算下列各小题
(1)5-(-6)-(+3)
(2)(-81)÷2
×
÷(-8)
(3)(
-
+
)÷(-
)
(4)-42÷(-2)-(-
)÷(-
)2
(5)1-2+3-4+5-6+…+2019-2020.
(1)5-(-6)-(+3)
(2)(-81)÷2
| 1 |
| 4 |
| 4 |
| 9 |
(3)(
| 7 |
| 9 |
| 5 |
| 6 |
| 3 |
| 4 |
| 1 |
| 36 |
(4)-42÷(-2)-(-
| 1 |
| 8 |
| 1 |
| 4 |
(5)1-2+3-4+5-6+…+2019-2020.
(1)5-(-6)-(+3)
=5+6-3
=11-3
=8;
(2)(-81)÷2
×
÷(-8)
=(-81)×
×
×(-
)
=2;
(3)(
-
+
)÷(-
)
=(
-
+
)× (-36)
=
×(-36)-
×(-36)+
×(-36)
=(-28)-(-30)+(-27)
=(-56)+30
=-26;
(4)-42÷(-2)-(-
)÷(-
)2
=-16÷(-2)-(-
)×16
=8-(-2)
=8+2
=10;
(5)1-2+3-4+5-6+…+2019-2020
=(1-2)+(3-4)+(5-6)+…+
=(-1)+(-1)+…+(-1)(1010个-1相加)
=-1010.
=5+6-3
=11-3
=8;
(2)(-81)÷2
| 1 |
| 4 |
| 4 |
| 9 |
=(-81)×
| 4 |
| 9 |
| 4 |
| 9 |
| 1 |
| 8 |
=2;
(3)(
| 7 |
| 9 |
| 5 |
| 6 |
| 3 |
| 4 |
| 1 |
| 36 |
=(
| 7 |
| 9 |
| 5 |
| 6 |
| 3 |
| 4 |
=
| 7 |
| 9 |
| 5 |
| 6 |
| 3 |
| 4 |
=(-28)-(-30)+(-27)
=(-56)+30
=-26;
(4)-42÷(-2)-(-
| 1 |
| 8 |
| 1 |
| 4 |
=-16÷(-2)-(-
| 1 |
| 8 |
=8-(-2)
=8+2
=10;
(5)1-2+3-4+5-6+…+2019-2020
=(1-2)+(3-4)+(5-6)+…+
=(-1)+(-1)+…+(-1)(1010个-1相加)
=-1010.
练习册系列答案
相关题目