2024年4月12日发(作者:今年高考数学试卷是几卷)

小学一年级上册数学试题

加法 与 减法

进位加法(凑十法口诀:看大数,分小数,凑成十,算得数.)

退位减法(破十法口诀:看大数,分出10,减小数,加剩数.)

借十法(十几减9,几加1;几减8,几加2;十几减7,几加3;十几减6,几加4;十

几减5,几加5;

十几减4,几加6;十几减3,几加7;十几减2,几加8;十几减1,几加9.)

一.“凑十法”:

1.“凑十法”是20以内进位加法的根本思绪.应用“凑十法”可以或许将20以

内的进位加法转化为学生所熟习的10加几的标题,从而化难为简.

那么“凑十法”在具体盘算中是若何“凑”十的呢,我们看以下例题:

在盘算9+4时,先把4分成1和3,然后9和1凑成10,10再加上3等于13;

这就是“凑十法”.

2.“凑十歌”:

1凑9 2凑8 3凑7来4凑6 5.5相凑正满10 做减做加想到它,又对又快真便

利!

3.“凑十法”具有很强的纪律性,不但可以在解决20以内进位加法的盘算顶用

到,在不进位加法中也可以用到.以下边例子解释:如在盘算14+5时,先把14分

成10和4,然后4和5先加等于9,然后再和前边的10相加等于19;

二、

“借十法”(破十法):

1.“借十法”是用在20以内退位减法中的盘算办法.应用“借十法”可将20以

内的退位减法转化为学生所熟习的10减几的标题,从而化难为简.

那么“借十法”在具体盘算中是若何“凑”十的呢,我们看以下例题:

在盘算13减4时,先斟酌个位3减4,不敷减,于是从十位借10来减,10减4得

6,再用6与个位数3相加等于9;

这就是“借十法”.

2.“借十法”口诀:借十法,很简略;

十几减9,几加1;十几减8,几加2;十几减7,几加3;十几减6,几加4;十几减5,

几加5;

十几减4,几加6;十几减3,几加7;十几减2,几加8;十几减1,几加9.

3.依据口诀与例题控制“借十法”.

凑 十 歌

一九一九好同伙, 二八二八手拉手, 三七三七真密切, 四六四六一路走. 五五

凑成一双手.

一加九,十只小蝌蚪, 二加八,十只花老鸭, 三加七,十只老母鸡, 四加六,十只

金丝猴, 五加五,十只大山君.

看到9想到1, 看到8想到2, 看到7想到3, 看到6想到4. 看到大数加小

数,.

一五6,二四6,三三6,四二6,五一6;6的构成没漏掉.

一六7,二五7,三四7,四三7,五二7,六一7;7的构成记细心.

一七8,二六8,三五8,四四8,五三8,六二8,七一8;8的构成记全它.

一八9,二七9,三六9,四五9,五四9,六三9,七二9,八一9; 9的构成全都有.

一九10,二八10,三七10,四六10,五五10,六四10,七三10,八二10,九一

10;10的构成共九句.

【 练 习 题. 一 】 (凑 十 法)

9 + 6 = 9 + 5 = 9 + 4 =

9 + 3 = 9 + 2 = 9 + 7 =

9 + 8 = 9 + 9 = 8 + 8 =

8 + 7 = 8 + 9 = 8 + 6 =

8 + 5 = 8 + 4 = 8 + 3 =

7 + 9 = 7 + 8 = 7 + 7 =

7 + 6 = 7 + 4 = 7 + 5 =

6 + 9 = 6 + 8 = 6 + 7 =

6 + 6 = 6 + 5 = 5 + 9 =

5 + 8 = 5 + 7 = 5 + 6 =

4 + 9 = 4 + 8 = 4 + 7 =

3 + 9 = 3 + 8 = 2 + 9 =

【 练 习 题. 二 】 (破十法)

11

– 9 = 17 – 9 = 16 – 9 = 15

12

9 = 13

4=

– 9 = 12 – 9 = 11

11

– 3 =

8 = 16

3 =

– 8 = 15 – 8 = 14

11

8 = 12

2 =

– 8 = 11 – 8 = 16

11

7 = 14

5 =

– 7 = 13 – 7 = 12

12

7 = 15

4=

– 6 = 14 – 6 = 13

13

– 6 = 11

– 4=

– 6 = 14 – 5 = 13

【 练 习 题. 三 】 (20以内退位减法)

破十法口诀:看大数,分出10;减小数,加剩数.

15 - 6 = 12 - 5 = 17

13 - 4 = 11 - 5 = 14

16 - 8 = 15 - 9 = 18

12 - 7 = 14 - 9 = 13

12 - 9 = 11 - 3 = 12

16 - 9 = 15 - 8 = 13

11 - 6 = 13 - 4 = 14

13 - 9 = 17 - 8 = 14

– 9 =

– 9 =

– 8 =

– 7 =

– 7 =

– 6 =

– 5 =

- 9 =

- 7 =

- 9 =

- 7 =

- 4 =

- 8 =

- 5 =

- 6=

18

14

17

13

15

11

12

【 练 习 题. 四 】 (凑十法)

1. 拆小数,凑大数

9 + 9 = 9 + 8 = 9 + 7 =

9 + 6 = 9 + 5 = 9 + 4 =

9 + 3 = 9 + 2 = 8 + 8 =

8 + 7 = 8 + 6 = 8 + 5 =

8 + 4 = 8 + 3 = 7 + 7 =

7 + 6 = 7 + 5 = 7 + 4 =

6 + 6 = 6 + 5 =

2. 拆大数,凑小数

9 + 9 = 8 + 9 = 7 + 9 =

6 + 9 = 5 + 9 = 4 + 9 =

3 + 9 = 2 + 9 = 8 + 8 =

7 + 8 = 6 + 8 = 5 + 8 =

4 + 8 = 3 + 8 = 7 + 7 =

6 + 7 = 5 + 7 = 4 + 7 =

6 + 6 = 5 + 6 =

15 - 6 = 14 - 5 = 13 - 4 =

【 练 习 题. 五 】 (凑十法)

【 练 习 题. 六 】 (凑十法)

【 练 习 题. 七 】 (凑十法)

【 练 习 题. 八 】 (凑十法)

12 - 3 = 11 - 2 = 16 - 7 =

17 - 8 = 18 - 9 = 16 - 8 =

15 - 7 = 17 - 9 = 14 - 6 =

13 - 5 = 12 - 4 = 11 - 3 =

16 - 9 = 15 - 8 = 14 - 7 =

13 - 6 = 11 - 4 = 12 - 5 =

15 - 9 = 14 - 8 = 13 - 7 =

12 - 6 = 11 - 5 = 14 - 9 =

13 - 8 = 12 - 7 = 11 - 6 =

13 - 9 = 12 - 8 = 11 - 7 =

12 - 9 = 11 - 8 = 11 - 9 =

【 练 习 题. 九 】 (凑十法)

1. 拆小数,凑大数,凑成10,再相加 .

9 + 8 = 9 + 7 = 9 + 6 =

9 + 5 = 9 + 4 = 9 + 3 =

9 + 2 = 8 + 7 = 8 + 6 =

8 + 5 = 8 + 4 = 8 + 3 =

7 + 6 = 7 + 5 = 7 + 4 =

6 + 5 =

【 练 习 题. 十 】 (凑十法)

2. 拆大数,凑小数,凑成10,再相加 .

8 + 9 = 7 + 9 = 6 + 9 =

5 + 9 = 4 + 9 = 3 + 9 =

2 + 9 = 7 + 8 = 6 + 8 =

5 + 8 = 4 + 8 = 3 + 8 =

6 + 7 = 5 + 7 = 4 + 7 =

5 + 6 =

3.

9 + 9 = 8 + 8 = 7 + 7 =

6 + 6 =

1. 拆小数,凑大数

9 + 9 = 9 + 8 = 9 + 7 =

9 + 6 = 9 + 5 = 9 + 4 =

9 + 3 = 9 + 2 = 8 + 8 =

8 + 7 = 8 + 6 = 8 + 5 =

8 + 4 = 8 + 3 = 7 + 7 =

7 + 6 = 7 + 5 = 7 + 4 =

6 + 6 = 6 + 5 =

2. 拆大数,凑小数

9 + 9 = 8 + 9 = 7 + 9 =

6 + 9 = 5 + 9 = 4 + 9 =

3 + 9 = 2 + 9 = 8 + 8 =

7 + 8 = 6 + 8 = 5 + 8 =

4 + 8 = 3 + 8 = 7 + 7 =

6 + 7 = 5 + 7 = 4 + 7 =

6 + 6 = 5 + 6 =

练 习 题. 十一 】 (凑十法)

练 习 题. 十二 】 (凑十法)


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