十五道简算,要有加分交换,结合律,或乘法分配,结合,交换律,就大神!!!

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请各位帮我各找十五道,第等式计算、简便计算还有竖式计算.总共45道题,
请各位帮我各找十五道,第等式计算、简便计算还有竖式计算.总共45道题,
要适合五年级的、
我先给50分,等会儿还会给.
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终于帮您找到了,
这是15道递等式计算:
(45-17)+(9-3)=28+6=34, (45-17)+(9-6)=28+3=31, (45-18)+(9-3)=27+6=33
(45-18)+(9-6)=27+3=30, (45-27)+(9-3)=18+6=24, (45-27)+(9-6)=18+3=21
(45-28)+(9-3)=17+6=23, (45-28)+(9-6)=17+3=20, (46-17)+(8-3)=29+5=34
(46-17)+(8-5)=29+3=32, (46-19)+(8-3)=27+5=32, (46-19)+(8-5)=27+3=30
(46-27)+(8-3)=19+5=24, (46-27)+(8-5)=19+3=22, (46-29)+(8-3)=17+5=22
这是简便运算:
1. (25%-695%-12%)*36
2. 3/4*3/5+3/4*2/5
3. (1-1/4+8/9)/7/9
4 2/3+1/6/3/24+2/21
5 1*8/15*3/5
6 10-3/4/9/10-1/6
7 [(1/3+1/2)/5/6-1/3]/1/7
8 2/3/5+3/5/2+3/4
9 1/[(2-2/3/1/2)]*2/5
10 3^2*3.25678
11 3^3-5
12 4^2-34%
13 3.25-315%
14 7^3+445%
15 12+5268.32-2569
不够的话还有:
1)2002+98+997+9996+99995
(2)0.1÷0.1÷0.1÷……÷0.1
50个0.1
(3)333……3^2
1998个3
(4)125×32×25
(5)0.000……024÷0.000……048
2001个0 2002个0
(6)1^3+2^3+3^3+……+10^3
(7)13579+35791+57913+79135+91357
(8)1111+2222+3333+4444
(9)12!÷5!÷4!÷3!÷280
(10)1÷4÷8÷1.25÷0.25
(11)2001^2-2000^2+1999^2-1998^2
(12)求1998×1998×1998×……×1998的个位数字 1998个1998
(13)求888……8除以26的余数
1999个8
竖式计算:
7.218÷36
5.93×0.76(保留三位小数)
16.32÷51
5.24÷7.2得数保留两位小数
3.54×13
20-5.674
5.84÷0.16
5.4÷0.036
8÷11(用循环小数表示商)
0.86×7
2.14×62
0.375×12
1.8×395
0.45×108
1.056×25
1.8×23
0.37×0.4
1.06×25
7×0.86
0.6×0.39
27×0.43
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设答对了x道,则答错了15-x道.
10x-2×(15-x)=120
10x-(30-2x) =120
12x =150
x =12.5
用去尾法x=12,则其他3题没答
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一元一次
8x-4(15-x)=72
8x-4*15+4x=72
12x=132
x=11
二元一次
(x+y=15
(8x-4y=72
解得:(x=11
(y=4
答对11题
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A. desk
B. table
C. chair
D. bench

2. The girl_____the bicycle is Jane.
A. riding on
B. driving in
C. riding in
D. driving on

3. _____ of his wealth, John is not very happy.
A. Beside
B. Because of
C. In spite of
D. Besides

4. Daddy was in a _____ for several days.
A. drama
B. coma
C. soma
D. tome

5. _____ it is from Bristol to Glasgow!
A. What long a way
B. What distance
C. How long way
D. How far

6. Tom is waiting _____ the doctor.
A. to see
B. to seeing
C. for see
D. for seeing

7. Her plane takes _____ at 3 p.m.
A. up
B. off
C. on
D. in

8. He sent _____ from Canada.
A. her a card
B. to her a card
C. card to her
D. to her card

9. My brother is four years older than me and someone I look _____ to, even though he is shorter than me.
A. up
B. down
C. below
D. over

10. Quite a lot of people watch TV only to _____ time.
A. waste
B. spend
C. kill
D. past

11. I'm not sure which restaurant _____.
A. to eat on
B. eating at
C. to eat at
D. for eating

12. Food alone is not the _____ of energy.
A. source
B. resource
C. force
D. grocer
13. Do not express shock for what you hear _____ matter how shocking it might seem.
A. not
B. never
C. no
D. none

14. The health seeking youths can following the of natural living.
A. principles
B. principals
C. principality
D. prince

15. His long _____ raised fears about his safety.
A. absent
B. absentee
C. absenting
D. absence
smili1年前4
zippo_king 共回答了18个问题 | 采纳率88.9%
B,A,B,B,D,
D,B,A,B,C,
D,A,C,A,D
英语用词的适当形式填空一共二十五道题希望能保证全对谢谢
英语用词的适当形式填空一共二十五道题希望能保证全对谢谢
look!our math's teacher ____ (sit) there and ____(read) the newspaper.we are ____(have) our ___ (one) chinese lesson.september 10th is ____(teach) day.he ____ (not want) ____ (spell) it any more.thank you for ____ (teach) us so well.there ___(be) a football game next week.we are ____ (think) about the names.she likes ___(go) _____ (fish).the ____(mean) of this word is important.he is_____ (call) james.can you help ____(clean) the house?chinese people are very ____(friend).this is _____(i) book...it ____ (take) a train to beijing.the woman are ___(eat) a new kind of fruit.would you like ____(come) with us.thank you for ____ (ask) us.it ___(have) something sweet inside.he enjoy ____(he).let's ____(take) a train to beijing.what are you ____ (do) now?she ____ (not like) watching tv.mike _____ (take) a bus to work every day.she is the _____(one) one to come to our classroomwhat about ____ (watch) a football game?
双龙1511年前2
T大明白 共回答了18个问题 | 采纳率94.4%
look!our math's teacher __is sitting__ (sit) there and _ reading___(read) the newspaper.
we are __having__(have) our _first__ (one) chinese lesson.
september 10th is __teachers'__(teach) day.
he __doesn't want__ (not want) __to speel__ (spell) it any more.
thank you for __teaching__ (teach) us so well.
there __will be_(be) a football game next week.
we are __thinking__ (think) about the names.
she likes __to go_(go) ___fishing__ (fish).
the __meaning__(mean) of this word is important.
he is___called__ (call) james.
can you help __to clean__(clean) the house?
chinese people are very __friendly__(friend).
this is ___my__(i) book...
it ___takes_ (take) a train to beijing.
the woman are __eating_(eat) a new kind of fruit.
would you like __coming__(come) with us.
thank you for __asking__ (ask) us.
it __has_(have) something sweet inside.
he enjoy __himself__(he).
let's __take__(take) a train to beijing.
what are you __doing__ (do) now?
she ___does not like _ (not like) watching tv.
mike ___takes__ (take) a bus to work every day.
she is the ____first_(one) one to come to our classroom
what about _watching___ (watch) a football game?
关于高一必修一期中前的,十五道,简单基础些.
我是水水我怕谁1年前1
可曼 共回答了21个问题 | 采纳率85.7%
1.若a>0,b>0且a的b次方=b的a次方,b=9a求a?
2.现有一种泉水样品,1.0 L这种泉水含有48.0mg Mg2+.那么,该泉水中Mg2+的物质的量浓度是多少?含1.0 mol Mg2+的这种泉水的体积是多少升?
3.在标准状况下,将11.2L HCl气体溶于水配成250mL溶液,该溶液中HCl的物质的量浓度为多少?
4.石块以2m/s的速度在冰上开始做匀速直线运动,10s后停止.那么它的平均速度是_m/s,滑行的距离是_m.
5.设集合A={-1,a},B={x∈Z|0NaCl+CO2+H2O
∵n(剩余盐酸)=0.05mol
所以n(气)=0.05mol
8.2C+O2=2CO
24--32--56
3---4
所以是CO
如果3:8则co2
很抱歉啊,时间来不及了,
初一代数式较难应用题十五道,附答案,过程要完整.
初一代数式较难应用题十五道,附答案,过程要完整.
好的加20分
goldenRetriever1年前2
qwjin7 共回答了18个问题 | 采纳率94.4%
11、已知一铁路桥长1000米,现有一列火车从桥上通过,测得火车从一开始上桥到车身过完桥共用1分钟,整列火车完全在桥上的时间为40秒,求火车的速度及火车的长度?
设火车的速度为a米/秒,车身长为b米
1分钟=60秒
60a=1000+b
40a=1000-b
100a=2000
a=20米/秒
b=60x20-1000
b=200米
车身长为200米.车速为20米/秒
12、甲乙两人以不变的速度在环形路上跑步,如果同时同地出发.相向而行,每隔2分钟相遇一次;如果同向而行,每隔6分钟相遇一次.已知甲比乙跑得快,甲乙每分各跑多少圈?
设甲每分钟跑X圈,乙每分钟跑Y圈.根据题意列方程得:
2X+2Y=1
6X-6Y=1
求得X=1/3 ,Y=1/6
答:甲每分钟跑1/3圈,乙每分钟跑1/6圈.
13、有五角,一元,二元三种人民币100张,合计100元.其中五角和二元的合计75元,每种人民币各几张?
设五角的有a张,一元的有b张,二元的则为100-a-b张
根据题意
0.5a+b+2×(100-a-b)=100(1)
0.5a+2×(100-a-b)=75(2)
(2)代入(1)
b=100-75=25张
代入(2)
0.5a+150-2a=75
75=1.5a
a=50
所以五角的有50张,一元的有25张,二元的25张
14、甲乙两人各自带了若干钱,如果甲得到乙的钱的一半,那么甲共有钱50.如果乙得到甲所有钱的三分之二,那么乙也共有钱50.问:甲乙各带了多少钱?
设甲带钱a元,乙带钱b元
a+1/2b=50(1)
b+2/3a=50(2)
化简
2a+b=100(3)
3b+2a=150(4)
(4)-(3)
2b=50
b=25元
a=50-25/2=37.5元
甲带了37.5元,乙带了25元
15、甲乙两人在银行共存款若干元,已知甲存款数的四分之一等于乙存款数的五分之一,又已知乙比甲多存了24元,甲乙各多少元?
设甲有a元,乙有b元
1/4a=1/5b
b-a=24
解得
a=96
b=120
16、甲乙共做一份工,甲先干了5天乙干了20天干完,如果让甲先刚20天乙干8天做完.那么甲乙同做需要多长时间
甲的工作效率为a,乙的工作效率为b
5a+20b=1(1)
20a+8b=1(2)
(1)×4-(2)
72b=3
b=1/24
5a=1-20/24
5a=1/6
a=1/30
甲乙合干需要1/(1/24+1/30)=24×30/54=40/3天
17、如图,用12m长的木料做一个中间有一条横档的日字形窗子.
(1)若使透进窗子的光线达到4.5m²,这时窗子的长和宽各是多少m?
(2)若使透进窗子的光线达到6m²,这时窗子的长和宽各是多少m?
(3)若使透进窗子的光线达到7m²,可能吗?为什么?
(1)设长为a米,宽为b米
根据题意
2a+3b=12(1)
ab=4.5(2)
由(1)
2a=12-3b
由(2)
2ab=9
(12-3b)b=9
4b-b²=3
b²-4b+3=0
(b-1)(b-3)=0
b=1或b=3
b=1时a=4.5
b=3时a=1.5
(2)
2a+3b=12
ab=6
解的过程省略
a=3
b=2
(3)
2a+3b=12
ab=7
2ab=14
(12-3b)×b=14
3b²-12b+14=0
判别式144-12×14=-24
十五道小数乘法和十五道小数除法 要答案 竖式的
十五道小数乘法和十五道小数除法 要答案 竖式的
最好写了竖式
永恒的水妖1年前1
落日伴人愁 共回答了4个问题 | 采纳率
说吧
小芳计划星期天要做二十五道数学题,上午做了五分之三,下午比上午少两道,晓芳下午做了多少道?
小芳计划星期天要做二十五道数学题,上午做了五分之三,下午比上午少两道,晓芳下午做了多少道?
甲数是六十,乙数比甲数的四分之三多四,乙数是多少
cctx9111年前6
追求的兔子 共回答了20个问题 | 采纳率75%
小芳计划星期天.
25*3/5=15题
15-2=13
甲数是六.
60*3/4+4=49
十五道脱试计算题附加答案分数乘法
心愿3211年前0
共回答了个问题 | 采纳率
语文五年级上册出十五道题目
无情不似多情1年前1
vz_ahce8sn37d5_ 共回答了11个问题 | 采纳率100%
一、判断下列词语的正误,对的打“√”;错误的标出错字,并改正.
临危不具( ) 豪不犹豫( ) 大显伸手( ) 轻盆大雨( ) 不动生色( ) 一如即往( ) 风期雪压( ) 不容争辨( ) 二、根据语境,给带点字选择合适的解释.
1.“破”在字典中的解释有:A.碎,不完整; B.揭穿; C.破费.在“破烂不堪”中应选( ).
2.“疾”在字典中的解释有:A.病; B.恨; C.疼痛;D.快,迅速.在“疾步向前”中应选( ). 三、把下面的词语按一定的顺序重新排列.
(1) 教科书 书 语文教科书 小学语文教科书
(2) 车 汽车 22路公共汽车 公共汽车
(3) 博兴县 山东省 滨州市 湖滨镇
四、判断下列句子运用了什么说明方法.
题 目 基础园 经典屋 阅览室
习作坊
总 评
成 绩
五年级语文试题 第2页(共6页)
(1)目前最大的鲸约有十六万公斤重. ( )
2)松鼠的叫声很响亮,比黄鼠狼的叫声还要尖些.( ) (3)它们常常直竖着身子坐着,像人们用手一样,用前爪往嘴里送东西. ( ) (4)这种玻璃叫“夹丝网防盗玻璃”,博物馆可以采用,银行可以采用,珠宝店也可以采用. ( ) 五、按要求写句子.
(1)圆明园建筑宏伟.圆明园收藏着最珍贵的历史文物.(用关联词语把
两句话合成一句话)
(2)还有什么别的话比这句最简单的话更能表达我此时的全部感情呢?
(把反问句改成陈述句)
(3)用修改符号在原句上修改病句.
在同学们的帮助下,使我顺利地完成了这个任务.
七年级上册(A卷60道题,B卷40道题,几何十道题,应用性综合十五道题,填空题30道,代数综合15道,计算30道)帅哥美
七年级上册(A卷60道题,B卷40道题,几何十道题,应用性综合十五道题,填空题30道,代数综合15道,计算30道)帅哥美女接来帮个忙!Thanks lot
猪猪大哥大1年前7
zpgood1987 共回答了19个问题 | 采纳率94.7%
振兴中学某班的学生对本校学生会倡导的“抗震救灾,众志成城”自愿捐款活动进行抽样调查,得到了一组学生捐款情况的数据,下图是根据这组数据绘制的同居图,图中从左到右各长方形的高度比是3:4:5:8:6,又知此次调查中捐款25元和30元的学生一共42人.
(1)他们一共调查了多少人?
(2)这组数据的众数、中位数各是多少?
(3)若该校共有1560名学生,估计全校学生捐款多少元?
某次数学竞赛共出了十五道选择题选对一题得四分每错一题扣两分若某同学的三十
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能不能把题目打完?很简单的解方程
得三十分?
设该同学答对x道题,则答错(15-x)道题
由题意得:4x-2(15-x)=30
解得:x=10,15-x=5
答:该同学答对10题,答错5题
数学课上老师计时一分钟做口算题丫丫做了十五道,红红做了十四道,亮亮做了十六道,他们谁做的快?把他们的成绩按一次顺序排列。
菲菲王SK1年前1
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亮亮第一,丫丫第二,红红第三
一道关于鸡兔同笼的问题城关区举行数学竞赛,共十五道题,每作对一道加8分,每作错一道减4分,XX作完了所有的题,得了84分
一道关于鸡兔同笼的问题
城关区举行数学竞赛,共十五道题,每作对一道加8分,每作错一道减4分,XX作完了所有的题,得了84分,他做对了几道.(用方程解)
天生痴呆1年前3
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8x-4(15-x)=84
12x=84+60
x=12
即:他做对了12道
一场比赛共十五道题。做对一题得八分,做错一题或不做倒扣四分,小刚共得84分。他做对了几道题?
RaymondTu1年前3
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错(8×15-84)÷(8+4)=3 对15-3=12
十五道心电图机与十二道心电图机的区别?
cbgh1年前1
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你说的应该是十二导联的心电图与十五导联的心电图机,区别是电极的数量.十二导联是指RA、LA、LF、avR、avL、avF、V1、V2、V3、V4、V5、V6,十五导联在十二的基础上加测后壁,V7腋后线与v4同一水平,V8左肩胛线与v4同一水平 v9:脊柱旁与v4同一水平
求上海世博会英文选择题15道!谁有关于上海世博会的题?英文版十五道!重赏!
zhangxinliang121年前1
雨中的风铃502 共回答了18个问题 | 采纳率88.9%
你先查资料,自己出15道题,发过来.我帮你翻译!
小亮,上午做了15道题,正确率是80%,下午做了二十五道题,正确率是92%。小亮这一天做题的正确率是多少?
菲彼岸1年前0
共回答了个问题 | 采纳率
求初一的五十道有理数计算题,二十五道整数的加减,二十五道化简求值题!(最好是有答案and过程)
daydream_1年前1
skwu 共回答了21个问题 | 采纳率95.2%
你可以去数学网站上找相关题目,有很多练习题
十五道四年级计算题
双四1年前2
txtx3 共回答了19个问题 | 采纳率84.2%
45+240÷12 124+78+22 100-35-25
(140-70)×54 63+84×2÷42 490÷7+24×5
26×6-110 345+99 (46-20)×30-90
25×27×4 15×7+85×7 (40-4)×25
125×64 2400÷80-14×2 108-(83+360÷60)
(420+48)÷(375-345) 290-(34×3+99)
142-54÷9+14 240÷16 75×4×25
407-99 16×76-76×6 99×53+53
720÷36÷2 103×35 450-2×(16+9)
245-(45+39) 28×25 473+59+27+1
98×99 125×(8×4)×5 41×25-25
88×125 420÷(205-198)×4 540÷2÷54
460÷(29-18÷3) 720÷36 (960-400)÷70
求十五道物理电学实验题及答案,最好条理清晰一点的,一定要有答案哦,要是全部的答案,快开学了!
求十五道物理电学实验题及答案,最好条理清晰一点的,一定要有答案哦,要是全部的答案,快开学了!
如果可以的话,最好外带十道物理电学问答题,真诚真诚!
不用找实验题了,来几道问答题就好了,o zZ
qdtkd1年前3
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1电流表为什么要串联?
答:电流表相当于一根导线.并联会造成短路.
2电压表为什么要并联?
答:电压表串联在电路中会造成断路,相当于电阻非常大的用电器.
3人体能承受的安全电压是多少?
答:小于等于36伏.
求十五道有答案的小数计算题(要求写出递等式)
求十五道有答案的小数计算题(要求写出递等式)
如上,必须是递等式!
xxxnnn1年前1
蝴蝶的天空 共回答了14个问题 | 采纳率78.6%
2.5×7.1×4 16.12×99+16.12 5.2×0.9+0.9
7.28×99+7.28 4.3×50×0.2 64-2.64×0.5
26×15.7+15.7×24 (2.275 +0.625)×0.28
3.94+34.3×0.2 1.2×(9.6÷2.4)÷4.8
8.9×1.1×4.7 2.7×5.4×3.9 3.6×9.85-5.46
8.05×3.4+7.6 6.58×4.5×0.9 2.8×0.5+1.58
32+4.9-0.9 4.8-4.8×0.5 (1.25-0.125)×8
4.8×100.1 56.5×99+56.5 7.09×10.8-0.8×7.09
4.85 + 0.35 ÷ 1.4 8.7 × 17.4 - 8.7 × 7.4
12.5×0.4×2.5×8 0.87×3.16+4.64 9.5×101
0.68 ÷(5.2 -3.5)× 1.25
40.5 ÷ 0.81 × 0.18 4.8 ×(15 ÷ 2.4) 2.13.×0.×8257
6.81+6.81×99 0.25×185×40 4.4×0.8-3.4×0.8
(9.37+9.37+9.37+9.37)× 2.5 4.2.×1.+1.×1.75
2.37×6.3+2.37×3.7 2.5×1.25×0.32 3.8×10.1
2.5×(3.8×0.04) 7.69×101 3.8×10.1
0.25×39+0.25 0.125×72 46×0.33+54×0.33
(8×5.27) ×1.25 6.81+6.81×99 0.25×185×40
6.8×0.75÷0.5 3.75÷0.125–2.75 1.53+23.4÷7.2
9.5×99 13.5×0.98 12.5×8.8
初二下册英语句型转换带答案的十五道
我要分七1年前1
五笔八六dd 共回答了26个问题 | 采纳率100%
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http://sh.yingyu.com/力推的,上面很全,而且网站也很干净啊.
你可以自己去看看,以下是我给你找的一些
Bruce will have to go back to Beijing next week.
Bruce will have to ______ ______ ______ next week.
42.Skating is quite different from skiing.
There are ______ ______ ______ ______ between skating and skiing,
43.He lent me a ruler last week.
I ______ ______ ______ ______ ______ last week.
44.He was too tired to walk.
He was ______ tired ______ he ______ ______.
45.Please tell me where to show our tickets.
Please tell me ______ ______ ______ ______ our tickets.
46.We will have two weeks' holiday.
We will have a ______ holiday..
47.I don't know how to call it in English.
I don't know ______ Englishmen ______ it.
48.“Are you a teacher?” he said.
He asked me ______ ______ ______ ______ ______.
49.Listen! Someone is knocking at the door loudly.
Listen! ______ ______ a ______ ______ ______ the door.
50. Mary doesn't know much about China.
Mary ______ ______ about China.
51.Don't forget my words.
Remember ______ ______ ______.
52.His father took a plane to the USA three days ago.
Three days ago his father ______ ______ the USA.
53.He is a scientist, too.
He is ______ a scientist.
54.Every one of us had a nice time last night.
_____ of us ______ ______ last night.
55.It's possible that she may catch a cold.
It's ______ ______ ______ to catch a cold
56.Not all balls are round in the USA.
______ ______ are round, but ______ ______ in the USA.
57.To learn a foreign language is not easy.
______ ______ ______ ______ learn a foreign language.
58.What do you think of the TV play?
______ ______ ______ ______ the TV play?
59.Why weren't you in the relay race?
Why ______ you ______ ______ ______ the relay race?
61.She hurried to school.
She ______ ______ school ______ ______ ______.
62.“Don't play with the cat any more, Jim.” Mum asked.
Mum told Jim ______ ______ ______ ______ the cat any more.
63.The boy was very clever. He could make a model plane alone.
The boy was clever ______ to make a model plane ______ ______.
64. She found him a very good pupil.
She found him ______ ______ a very good pupil.
She found he ______ ______ ______ ______ ______.
65. People usually call Catherine Kate for short.
Kate ______ ______ ______ Catherine.
66. Paul is the best basketball player on the city team.
______ ______ basketball ______ ______ Paul on the city team.
67. It's best for you to come to China in spring.
______ ______ ______ to China in spring.
68.How is the weather in Nanjing?
______ the weather ______ in Nanjing?
69.The snow was very heavy last night.
It ______ very ______ last night.
70.In much of China, spring lasts from March to May.
In ______ ______ of China, spring ______ ______ March and ______ ______
______ May.
71.Mother doesn't let me go out alone at night.
Mother ______ me ______ ______ out alone at night.
72.Shanghai's temperature will be 2 to 8 and there will be cloud.
Shanghai will be ______ and ______ temperature will ______ 2 to 8.
Shanghai will ______ a ______ day ______ temperature ______ 2 to 8.
73. I'm sorry to trouble you.
I'm sorry ______ ______ you.
74. The man went playing tennis in the morning and he did it every day.
The man went playing tennis in the morning and it ______ every day.
75. They were drinking happily. Just at that time, a policeman came in.
They were drinking happily______ ______ ______ ______ ______.
76. I don't think you have to use them today.
I don't think you ______ ______ ______ them today.
77. We are tired of his long speech.
We ______ ______ ______ ______ his long speech.
78. When she was in the park, she could hear the birds. The birds were singing
beautifully.
When she was in the park, she could hear ______ ______ ______ ______.
79. You may have the traffic accident if you don't drive carefully.
Don't drive ______, ______it may _______ the traffic accident.
80. Read English as often as possible.
Read English as often as ______ ______.
改写句子参考答案
41.works as an assistant 42.return to Beijing 43.quite a few differences 44.borrowed a ruler from him 45.so, that, couldn’t walk 46.where we should show 47.two-week 48.how, call 49.if I was a teacher 50.There is, loud knock at/on 51.knows little 52.what I said 53.flew to 54.also 55.Each, enjoyed ourselves 56.possible for her 57.Some balls, some aren’t 58.It isn’t easy to 59.How do you like 60.didn’t, take part in 61.went to, in a hurry 62.not to play with 63.enough, by himself 64.to be, was a very good pupil 65.is short for 66.Nobody plays, better than/ The best, player is 67.You’d better come 68.What’s, like 69.snowed, heavily 70.most parts, starts in, goes on to 71.stops, from going 72. cloudy, its/the, be, have, cloudy, with, from 73.to disturb 74.happened 75.when a policeman came in 76.need to use 77.are fed up with 78.the birds singing beautifully 79.carelessly, or, cause 80.you can
初二上半年数学。十五道根号的计算题。求学霸。
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?题呢,我没看到( ⊙ o ⊙ )啊!你出,然后还有答案。1:根号50+根号1/2-(根号12+根号3)/根号27 答案: (11/2根号2) 2:((2根号2)-3)*(2根号2)+3)答案:-1 3:((3根号2)-1)的平方+根号8 答案:19-4根号2 4:3根号3((-3根号3)+(根号12))答案:9 5:根号18-根号12+3根号1/3 答案:3根号2-根号3...
长天小学举行一次数学竞赛,共十五道题,答对一题得八分,错一题倒扣一分,刘敏敏共得72分,他做对了多少道题?
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设答对了x题,则有:
8x-(15-x)=72;
9x-15=72;
9x=87;
x=87/9;
题目有问题
三位数除以两位数的算试,出十五道
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300÷60,350÷70,250÷50200÷40,400÷80,450÷90100÷50,500÷50,600÷60700÷70,800÷80,900÷90100÷25,600÷30,900÷30