1樓:匿名使用者
1.(1/69+2/71)*23+25除以71
2.(1+1/2)*(1-1/2)*1+1/3)*(1-1/3)*........*(1+1/9)*(1-1/9)
3.1/2*3+1/3*4+.......+1/19乘20
4.1/27+505/2727+131313/272727
5.100-98+96-94+....+4-2
1.(1/69+2/71)乘23+25除以71
=1/69*23+2/71*23+25/71
=1/3+(46/71+25/71)
=1/3+1
=4/3
2.(1+1/2)乘(1-1/2)乘(1+1/3)乘(1-1/3)乘........乘(1+1/9)乘(1-1/9)
=3/2*1/2*4/3*2/3...*10/9*8/9
=1/2*10/9
=5/9
3.1/2乘3+1/3乘4+.......+1/19乘20
=1/2-1/3+1/3-1/4+...+1/19-1/20
=1/2-1/20
=9/20
4.1/27+505/2727+131313/272727
=1/27+5*101/(27*101)+13*10101/(27*10101)
=1/27+5/27+13/27
=19/27
5.100-98+96-94+....+4-2
=(100-98)+(96-94)+...(4-2)
=2+2+...+2(共有25個)
=2*25
=5010-2.65=
0.9×0.08=
528-349=
6+14.4=
24÷0.04=
12.34-2.3=
0÷3.8=
0.77+0.33=
7÷1.4=
67.5+0.25=
7.2÷8×4=
5-1.4-1.6=
400÷125÷8=
1.9×4×0.5=
80×0.125=
2×5-6+2=
3.2×7÷3.2×7=
4 +3.2+5 +6.8 25×(8×0.4)×1.25 7
1125-997 998+1246+9989 (8700+870+87)÷87
125×8.8 1.3+4.25+3.7+3.75 17.15-(3.5-2.85)
3.4×99+3.4 4.8×1.01 0.4×(2.5÷73)
(1.6+1.6+1.6+1.6)×25
12.3-2.45-5.7-4.55 2 + 0.125×0.25×64
64.2×87+0.642×1300 78×36+7.8×741-7
0.125× +0.5 2.42 +4.58 -43×0
25÷100 4.25-3 -(2 -1 )
1.25*17.6+36.1/0.8+2.36*12.5
=(5/4)*17.6+36.1*(5/4)+23.6*(50/4)
=176/8+361/8+236/8
=773/8=96.625
7.5*2.3+1.9*2.5
=7.5*(1.9+0.4)+1.9*2.5
=(7.5+2.5)*1.9+7.5*0.4
=19+3 =22
2004/2003*2005
=(2004/2003)*(2003+2)
=2004+4008/2003
276*543-267/276+543*275
=543*(276+275)-267/276
=543*551-267/276
17/51+ (68/1+51/2)*17
五十二又二十五分之十一×79.45+159×47.56+七十九又二十分之十一×52.44
=52.44×79.45+159×47.56+79.55×52.44
=52.44×(79.45+79.55)+159×47.56
=52.44×159+159×47.56
=159×(52.44+47.56)
=159×100
=15900
2002+2001-2000-1999+1998+1997-1996-1995+……+2+1
=(2002-2000)+(2001-1999)+(1998-1996)+(1997-1995)+……+(6-4)+(5-3)+2+1
=2+2+2+2+……+2+2(從3-2002共2000個數,所以有1000個2)+2+1
=1000×2+2+1
=2003
5兩題均用到一個轉換式1/(a×b)=1/(b-a)×(1/a-1/b)
如1/15=1/(3×5)=1/(5-3)×(1/3-1/5)=1/2×(2/15)=1/15可驗證一下
(1×2分之一)+(2×3分之一)+(3×4分之一)+……+(10×11分之一)
=1/(1×2)+1/(2×3)+1/(3×4)+……+1/(10×11)
=(1-1/2)+(1/2 - 1/3)+(1/3 - 1/4)+……+(1/10 - 1/11)
=1-1/11
=10/11
三分之一+十五分之一+三十五分之一+六十三分之一+九十九分之一
=1/(1×3)+1/(3×5)+1/(5×7)+1/(7×9)+1/(9×11)
=1/2×(1-1/3)+1/2×(1/3-1/5)+1/2×(1/5-1/7)+1/2×(1/7-1/9)+1/2×(1/9-1/11)
=1/2×(1 - 1/3 + 1/3 - 1/5 + 1/5 - 1/7 + 1/7 - 1/9 + 1/9 - 1/11)
=1/2×(1-1/11)
=1/2×10/11
=5/11
一又二分之一-六分之五+十二分之七-二十分之九+三十分之十一-四十二分之十三+五十六分之
(根據提示,1又1/2=1+1/2,+1/2+1/3=5/6……)
=(1+1/2)-(1/2+1/3)+(1/3+1/4)-(1/4+1/5)+(1/5+1/6)-(1/6+1/7)+(1/7+1/8)
=1+ 1/2 - 1/2 - 1/3 + 1/3 + 1/4 - 1/4 - 1/5 + 1/5 + 1/6 - 1/6 - 1/7 + 1/7 + 1/8
=1+1/8
=9/8
1.7+150 +3.98 17.625-(4.4+58 ) 3.35×6.47×2+6.7×3.6
125×(8+0.8+0.08) 910 ×(56 -49 ÷45 )
2.8×0.4+10.2÷3.4 35 ÷〔78 -(25 +38 )〕 18.7-3.375-6.625
(9+92+93)×0.01 13.5×[1.5×(1.07+1.93)]
2樓:非非元
1+1=2 2+2=4 3+3=6 4+4=8 5+5=10
3樓:麼珉樊合
你上面的算式有點問題,應該是下面這樣
=1+(2+1/6)+(3+1/12)+(4+1/20)+(5+1/30)+(6+1/42)+(7+1/56)+(8+1/72)+(9+1/90)
=45+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90
=45+1/2-1/10
=45+2/5
4樓:倫紹闞綺美
1.(1/69+2/71)乘23+25除以71=1/69*23+2/71*23+25/71=1/3+(46/71+25/71)
=1/3+1
=4/3
2.(1+1/2)乘(1-1/2)乘(1+1/3)乘(1-1/3)乘........乘(1+1/9)乘(1-1/9)
=3/2*1/2*4/3*2/3...*10/9*8/9=1/2*10/9(中間的都約去了)
=5/9
3.1/2乘3+1/3乘4+.......+1/19乘20=1/2-1/3+1/3-1/4+...+1/19-1/20=1/2-1/20
=9/20
4.1/27+505/2727+131313/272727=1/27+5*101/(27*101)+13*10101/(27*10101)
=1/27+5/27+13/27
=19/27
5.100-98+96-94+....+4-2=(100-98)+(96-94)+...(4-2)=2+2+...+2(共有25個)
=2*25=50
5樓:
1.(1/69+2/71)乘23+25除以71
2.(1+1/2)乘(1-1/2)乘(1+1/3)乘(1-1/3)乘........乘(1+1/9)乘(1-1/9)
3.1/2乘3+1/3乘4+.......+1/19乘20
4.1/27+505/2727+131313/272727
5.100-98+96-94+....+4-2
小學六年級簡便計算
1.(1/69+2/71)乘23+25除以71
=1/69*23+2/71*23+25/71
=1/3+(46/71+25/71)
=1/3+1
=4/3
2.(1+1/2)乘(1-1/2)乘(1+1/3)乘(1-1/3)乘........乘(1+1/9)乘(1-1/9)
=3/2*1/2*4/3*2/3...*10/9*8/9
=1/2*10/9(中間的都約去了)
=5/9
3.1/2乘3+1/3乘4+.......+1/19乘20
=1/2-1/3+1/3-1/4+...+1/19-1/20
=1/2-1/20
=9/20
4.1/27+505/2727+131313/272727
=1/27+5*101/(27*101)+13*10101/(27*10101)
=1/27+5/27+13/27
=19/27
5.100-98+96-94+....+4-2
=(100-98)+(96-94)+...(4-2)
=2+2+...+2(共有25個)
=2*25
=50小學六年級數學總複習資料(六) 【簡便計算】
班級: 姓名:
一、口算下面各題。(23分)
10-2.65= 0.9×0.08= 528-349= 6+14.4= 24÷0.04=
12.34-2.3= 0÷3.
8= 0.77+0.33= 7÷1.
4= 67.5+0.25=7.
2÷8×4= 5-1.4-1.6= 400÷125÷8= 1.
9×4×0.5=
80×0.125= 3× = 6 6= 2 -( + )= 10 2=
3.2×7÷3.2×7= ( - )×12= 187.7×11-187.7= 1- 62.5%=
二、寫出下列每題在簡便運算時所運用的定律或性質(12分)
4 +3.2+5 +6.8 25×(8×0.4)×1.25 7 -(2 - )
( ) ( ) ( )
( + + )×72 93.5÷3 16÷2.5
( ) ( ) ( )
三、用簡便方法計算。(65分)
1125-997 998+1246+9989 (8700+870+87)÷87
125×8.8 1.3+4.25+3.7+3.75 17.15-(3.5-2.85)
3.4×99+3.4 4.8×1.01 0.4×(2.5÷73)
(1.6+1.6+1.6+1.6)×25 ( + - )÷
12.3-2.45-5.7-4.55 2 + 0.125×0.25×64
64.2×87+0.642×1300 78×36+7.8×741-7 17+ 8
0.125× +0.5 2.42 +4.58 -43
25÷100 4.25-3 -(2 -1 )
(1)1.25*17.6+36.1/0.8+2.36*12.5
1.25*17.6+36.1/0.8+2.36*12.5
=(5/4)*17.6+36.1*(5/4)+23.6*(50/4)
=176/8+361/8+236/8
=773/8=96.625
(2)7.5*2.3+1.9*2.5
7.5*2.3+1.9*2.5
=7.5*(1.9+0.4)+1.9*2.5
=(7.5+2.5)*1.9+7.5*0.4
=19+3 =22
(3)2004/2003*2005
2004/2003*2005
=(2004/2003)*(2003+2)
=2004+4008/2003
(4)276*543-267/276+543*275
276*543-267/276+543*275
=543*(276+275)-267/276
=543*551-267/276
(5)17/51+ (68/1+51/2)*17
17/51+ (68/1+51/2)*17
後面的做不下去了,好像有一些沒有簡便方法,不知道你題目有沒有抄錯,你的68/1中的68是分子還是分母呀?應該是分母都對
(6)(3.25-0.8*8/5)/(6又4/1-3.5)
是6又1分之4嗎?應該是6又4分之1吧
1)五十二又二十五分之十一×79.45+159×47.56+七十九又二十分之十一×52.44
=52.44×79.45+159×47.56+79.55×52.44
=52.44×(79.45+79.55)+159×47.56
=52.44×159+159×47.56
=159×(52.44+47.56)
=159×100
=15900
3)2002+2001-2000-1999+1998+1997-1996-1995+……+2+1
=(2002-2000)+(2001-1999)+(1998-1996)+(1997-1995)+……+(6-4)+(5-3)+2+1
=2+2+2+2+……+2+2(從3-2002共2000個數,所以有1000個2)+2+1
=1000×2+2+1
=2003
4,5兩題均用到一個轉換式1/(a×b)=1/(b-a)×(1/a-1/b)
如1/15=1/(3×5)=1/(5-3)×(1/3-1/5)=1/2×(2/15)=1/15可驗證一下
4)(1×2分之一)+(2×3分之一)+(3×4分之一)+……+(10×11分之一)
=1/(1×2)+1/(2×3)+1/(3×4)+……+1/(10×11)
=(1-1/2)+(1/2 - 1/3)+(1/3 - 1/4)+……+(1/10 - 1/11)
=1-1/11
=10/11
5)三分之一+十五分之一+三十五分之一+六十三分之一+九十九分之一
=1/(1×3)+1/(3×5)+1/(5×7)+1/(7×9)+1/(9×11)
=1/2×(1-1/3)+1/2×(1/3-1/5)+1/2×(1/5-1/7)+1/2×(1/7-1/9)+1/2×(1/9-1/11)
=1/2×(1 - 1/3 + 1/3 - 1/5 + 1/5 - 1/7 + 1/7 - 1/9 + 1/9 - 1/11)
=1/2×(1-1/11)
=1/2×10/11
=5/11
6)一又二分之一-六分之五+十二分之七-二十分之九+三十分之十一-四十二分之十三+五十六分之十五
(根據提示,1又1/2=1+1/2,+1/2+1/3=5/6……)
=(1+1/2)-(1/2+1/3)+(1/3+1/4)-(1/4+1/5)+(1/5+1/6)-(1/6+1/7)+(1/7+1/8)
=1+ 1/2 - 1/2 - 1/3 + 1/3 + 1/4 - 1/4 - 1/5 + 1/5 + 1/6 - 1/6 - 1/7 + 1/7 + 1/8
=1+1/8
=9/8
六年級簡便計算
1 3 3 4 2 5 5 7 7 8 9 20 10 21 11 24 19 35 1 3 3 4 2 5 5 7 7 8 4 20 5 20 3 21 7 21 3 24 8 24 5 35 14 35 1 3 3 3 4 1 4 2 5 1 5 2 5 5 7 1 7 1 7 7 8 1 8 ...
小學六年級數學簡便運算計算題,小學六年級簡便運算計算題
我們四年級不是有買過一本 口算十分鐘 嗎?那裡面有很多題型啊,隨便換個數或者把小括號移個位置就可以 了。6.28 5.74 3.72 5.26 48 6.2 6.2 52 25 125 4 8 16.9 5.6 4.4 9.08 5.7 1.08 5.8 99 5.8 360 1.2 50 40 1...
六年級簡便計算9 8 65 2 1 25 12
9.8 62.5 1.25 12.5 0.625 18 9.8 6.25 12.5 12.5 0.625 18 12.5 9.8 6.25 6.25 1.8 12.5 6.25 8 12.5 8 6.25 100 6.25 625 這個還用過程?9.8 65.2 1.25 798.7 12.5 0....