口算．14+24=910-910=1112-812=47+27=58-38=15+35=69+39=99-12=1-47=56-16=78+28=310+510=

小学数学 2024-07-22 03:34:17

口算．

1

4

+

2

4

=

9

10

-

9

10

=

11

12

-

8

12

=

4

7

+

2

7

=

5

8

-

3

8

=

1

5

+

3

5

=

6

9

+

3

9

=

9

9

-

1

2

=

1-

4

7

=

5

6

-

1

6

=

7

8

+

2

8

=

3

10

+

5

10

=

考点：分数的加法和减法 专题：运算顺序及法则 分析：按照分数加减法的计算法则直接计算得出答案即可． 解答：

解：

1

4

+

2

4

=

3

4

9

10

-

9

10

=0

11

12

-

8

12

=

1

4

4

7

+

2

7

=

6

7

5

8

-

3

8

=

1

4

1

5

+

3

5

=

4

5

6

9

+

3

9

=1

9

9

-

1

2

=

1

2

1-

4

7

=

3

7

5

6

-

1

6

=

2

3

7

8

+

2

8

=

9

8

3

10

+

5

10

=

4

5

点评：掌握分数加减法的计算法则是解决问题的关键．