4--1 8能简便的要简便)12--11 15 8 45

2020-11-23 21:17:03 字数 7028 阅读 2885

1楼:凌月霜丶

3/8+(3/4--1/8)=

=3/8+1/8+3/4

=1/4+3/4

=112--11/15×8/45×15/11==11-11/15*15/11*8/45

=11-8/45

=10又37/45

3/11÷4/7+8/11×7/4

=3/11*7/4+8/11*7/4

=7/4*(3/11+8/11)

=7/4*1

=7/4

2楼:匿名用户

第一题3/4通分等于6/8

(1/15+1/21)×105 45÷5/7÷7/8 8/13÷7-1/7×6/13 1/5×5/8-1/5÷8/3 3/5÷5/8+2/5÷5/8简便运算

3楼:叫啥知不道

(1/15+1/21)×105

=(1/15)

*(15*7)+(1/21)*(21*5)=7+5

=1245÷5/7÷7/8

=5*9*(7/5)*(8/7)

=9*8

=728/13÷7-1/7×6/13

=8/13*(1/7)-6/13*(1/7)=(8/13-6/13)*(1/7)

=2/13*1/7

=2/91

1/5×5/8-1/5÷8/3

=1/5*5/8-1/5*3/8

=1/5*(5/8-3/8)

=1/5*1/4

=1/20

3/5÷5/8+2/5÷5/8

=(3/5+2/5)*(8/5)

=1*8/5

=8/5

x-1/2x=5/8

1/2x=5/8

x=5/8*2

x=5/4

4/5x÷2=7/16

4/5x=7/16*2

x=7/8*5/4

x=35/32

1/4x+1/3x=5/18

7/12x=5/18

x=5/18*12/7

x=10/21

1/8x÷3/10=5/18

1/8x=5/18*3/10

x=1/12*8

x=2/3

4/5x-3/4x=25

(16/20-15/20)*x=25

x=25/(1/20)

x=500

4楼:匿名用户

(1/15+1/21)×105=7+5=12

45÷5/7÷7/8 =45*7/5*8/7 =45*8/5=72

8/13÷7-1/7×6/13 =(8-6)/(13*7)=2/91

1/5×5/8-1/5÷8/3=5/40-3/40=2/40=1/20

3/5÷5/8+2/5÷5/8=(3/5+2/5)÷5/8 =8/5

x-1/2x=5/8 , x=5/4

4/5x÷2=7/16 , 2/5 x= 7/16, x=35/32

1/4x+1/3x=5/18 , 7/12 x = 5/18, x=10/21

1/8x÷3/10=5/18 , 1/8 x =5/18*3/10, x=2/3

4/5x-3/4x=25, (16-15)/20 x =25, x=500

能用简便方法计算的用简便方法计算:1,201x45 2,24乘(3/8+1/6-1/12)

5楼:匿名用户

201x45

=(200+1)x45

=200x45+1x45

=9000+45

=9045

24乘(3/8+1/6-1/12)

=24x3/8+24x1/6-24x1/12=9+4-2=11

6楼:匿名用户

201×45

=(200+1)×45=200×45+1×45=9000+45=9045;24×(3/8+1/6-1/12)=24×3/8+24×1/6-24×1/12

=9+4-2=11

7楼:却妮本小雯

原式=4/15x45+5/9x45-17/45x45=4x3+5x5-17x1

=12+25-17

=37-17

=20供参考。

简便计算: 1. 3.625÷5/32+6又2/5×3/8+6.4 2. 45÷5/8+1.6+4.4×1又3/5 3. 8/9×【3/4-(7/16-0.25)】

8楼:匿名用户

1. 3.625÷5/32+6又2/5×3/8+6.4=3.625×32/5+

6.4×3/8+6.4×1

=3.625×6.4+6.4×0.375+6.4×1=6.4×(3.625+0.375+1)

=6.4×5

=322. 45÷5/8+1.6+4.

4×1又3/5=45×8/5+1.6×1+4.4×1.

6=45×1.6+1.6×1+4.

4×1.6=1.6×(45+1+4.

4)=1.6×50.4

=1.6×(50+0.4)

=1.6×50+1.6×0.4

=80+0.64

=80.64

3. 8/9×【3/4-(7/16-0.25)】=8/9×【3/4-(7/16-1/4)】=8/9×【3/4-7/16+1/4】

=8/9×【3/4+1/4-7/16】

=8/9×【1-7/16】

=8/9×9/16

=1/2

4. 6.3×29又4/5+2.98×37=6.3×29.8+2.98×37

=63×2.98+2.98×37

=2.98×(63+37)

=2.98×100

=298

5. 3.6×31又2/5+314×0.

63+3.14=3.6×31.

4+314×0.63+3.14=36×3.

14+3.14×63+3.14×1=3.

14×(36+63+1)

=3.14×100

=314

6. 72×61又3/10+73.8*2又4/5=72×61.3+73.8×2.8

=72×61.3+(72×1.025×2.8)=72×61.3+72×(1.025×2.8)=72×61.3+72×2.87

=72×(61.3+2.87)

=72×64.17

=4620.24

7. 1/5+51/5+501/5+5001/5+50001/5=1/5+10又1/5+100又1/5+1000又1/5+10000又1/5

=(10+100+1000+10000)+(1/5+1/5+1/5+1/5+1/5)

=11110+1

=11111

9楼:妙酒

1. 3.625÷5/32+6又2/5×3/8+6.4=3又5/8x32/5+32/5x3/8+6.4=(3又5/8+3/8)x6.4+6.4

=4x6.4+6.4

=(4+1)x6.4

=5x6.4

=322. 45÷5/8+1.6+4.4×1又3/5=45x8/5+8/5+4.4x8/5

=(45+1+4.4)x8/5

=(50+0.4)x8/5

=50x8/5+0.4x8/5

=80+0.64

=80.64

3. 8/9×【3/4-(7/16-0.25)】=8/9x(3/4-7/16+1/4)

=8/9x(1-7/16)

=8/9x9/16

=1/2

4. 6.3×29又4/5+2.98×37=6.3x29.8+29.8x0.1x37=29.8x(6.3+3.7)

=29.8x10

=298

5. 3.6×31又2/5+314×0.

63+3.14=3.6x31.

4+31.4x10x0.63+31.

4x0.1=31.4x(3.

6+6.3+0.1)

=31.4x10

=314

6. 72×61又3/10+73.8*2又4/5=72x61.3+73.8x2.8

=4413.6+206.64

=4620.24

7. 1/5+51/5+501/5+5001/5+50001/5=1/5+10又1/5+100又1/5+1000又1/5+10000又1/5

=10000+1000+100+10+1/5x5=11111

10楼:围观者

1.原式=3.625*(32/5)+(32/5)*0.375+32/5=(32/5)*(3.625+0.375+1)=(32/5)*5=32

2.原式=45*(8/5)+8/5+4.4*(8/5)=(8/5)*(45+1+4.4)=80.64

3.原式=8/9 *(3/4-7/16+1/4)=8/9 * 9/16=1/2

4.原式=6.3*29.8+2.98*37=2.98*(63+37)=2.98*100=298

5.原式=3.6*31.4+314*0.63+3.14=3.14*(36+63+1)=3.14*100=314

6.题没抄错吧

7.原式=1/5+10+1/5+100+1/5+1000+1/5+10000+1/5=11111

小学四年级的数学题(应用题 笔算等)

11楼:樱雪妃媗

32.8+19= 0.51÷17= 240÷30= 1000×0.8=

3.06+0.2= 0.67+1.24= 8×125= 7-6.28=

8.2-0.01= 99×23= 50×4= 5÷1000=

0.42+9.5= 65×25×4= 0.08÷100= 10×0.5=

1.82-0.63= 4.5+1.5= 1-0.63= 231-99=

二、填空(每空1分,共15分)

1.一个数,亿位上是6,百万位上是4,十万位上是5,千位上是8,其余各位上都是0,这个数写作( ),读作( ),最高位的计数单位是( ).

2.三百二十三亿六千八百七十万,写作( ),改写成用“亿”作单位的数约是( ).

3.25米60毫米=( )毫米

4.3.45平方米=( )平方米( )平方分米

5.150分=( )时( )分

6.15吨60千克=( )千克

7.自然数和0都是( )数.

最小的数是( ).

三、判断(正确的在括号里划“√”,错误的在括号里划“×”)(每题1分,共10分)

1.小数加法的意义与整数加法的意义完全相同. ( )

2.不相交的两条直线叫做平行线. ( )

3.在有余数的除法里,除数一定比余数大. ( )

4.0.47扩大10倍等于470缩小100倍. ( )

5.角的大小与边的长短有关. ( )

6.小数一定比整数小. ( )

7.最大的四位数比最小的五位数多1. ( )

8.有二个角是锐角的三角形叫锐角三角形. ( )

9.57×101的简便算法是57×100+57=5757. ( )

10.a×b的积一定大于a. ( )

四、计算题(共33分)

1.计算下面各题并验算.(每题2分,共4分)

①802×11 ②329÷48

2.求未知数x.(每题2分,共8分)

①x×123=1845 ②x+0.05=3.528

③x-3.6=7.89 ④8064÷x=144

3.计算下面各题,能用简便算法的用简便算法(每题3分,共21分)

①3871-(1080-740)×7 ②5175÷207+102×9

③0.9+1.08+0.92+0.1 ④13.59-6.91-0.09

⑤983×(3.8+2.2)+0.237×1000

⑥0.8×(35+65)×5÷100

⑦30-[17.8+(6.2+38÷10)]

五、列式计算(每题3分,共12分)

1.10减去5.6与1.4的和,所得的差去除246,商是多少?

2.6.2减去2.4与1.3的和,所得的差乘以100,积是多少?

3.21乘以32与88的积,所得的积再减去9136,差是多少?

4.357除以7的商,加上1000与0.875的积,和是多少?

六、应用题(每题5分,共20分)

1、某小学三年级和四年级要给620棵树浇水,三年级每天浇40棵,浇了8天;剩下的由四年级来浇,5天浇完,平均每天浇多少棵?

2.3台织布机4小时织布336米,照这样计算,1台织布机8小时织布多少米?

3.甲乙两地相距560千米,一辆汽车从甲地开往乙地,每小时行48千米,另一辆汽车从乙地开往甲地,每小时行32千米.两车从两地相对开出5小时后,两车相距多少千米?

4.一段公路原计划20天修完.实际每天比原计划多修45米,提前5天完成任务.原计划每天修路多少米?

参***

一、(略)

二、1.604508000,六亿零四百五十万八千,亿.

2.32368700000,324亿.

3.25060

4.3,45

5.2,30

6.15060

7.整三、1.√ 2.× 3.√ 4.√ 5.× 6.× 7.× 8.× 9.√ 10.×

四、1.计算下面各题并验算

①8822 ②6……41

2.求未知数x

①x=15 ②x=3.479 ③x=11.49 ④x=56

3.计算下面各题,能用简便算法的用简便算法

①1491 ②943 ③3 ④6.59 ⑤6135 ⑥4 ⑦2.2

五、1.82 2.250 3.50000 4.926

六、1.60棵 2.224米 3.160千米 4.45×(20-5)÷5=135(米)

4(3 3)X36 ,3/7X1/4÷3/4 (3/8+2/3)X36 7/5X2/3+14/15÷1/9 13/12÷(3/4+1/3) 给答案,我看对不对,如果有过程的

1楼 匿名用户 3 7x1 4 3 4 3 7x1 4x4 3 1 7 3 8 2 3 x36 3 8x36 2 3x36 37 5 7 5x2 3 14 15 1 9 14 15 14 15x9 14 15 1 9 9又1 3 13 12 3 4 1 3 13 12x12 13 1 简算 3 4 ...