Question

直接寫得數(shù)． 5 6 + 5 6 =	5 17 + 7 17 =	1- 2 7 =	7 16 - 5 16 =
19 91 - 12 91 =	7 13 + 6 13 =	19 17 -1=	7 16 - 3 16 =
3-1 1 7 =	7 5 + 6 5 =

Answer 1

分析：把3-1

1

7

和

19

17

-1中的整數(shù)化成分數(shù)，此題就都成了同分母分數(shù)的加減法運算，然后按同分母分數(shù)加減法的法則計算：只把分子相加減，分母不變．

解答：解：

5

6

+

5

6

=

5

3

；              

5

17

+

7

17

=

12

17

；             1-

2

7

=

5

7

；          

7

16

-

5

16

=

1

8

；

19

91

-

12

91

=

1

13

；               

7

13

+

6

13

=1；               

19

17

-1=

2

17

；         

7

16

-

3

16

=

1

4

；

3-1

1

7

=1

6

7

；                 

7

5

+

6

5

=

13

5

．

點評：此題考查了同分母分數(shù)相加減的法則：只把分子相加減，分母不變．但要注意，能約分的要約分．