(完整版)五年级上册数学简便计算
(完整word版)五年级上册小数简便运算总结,推荐文档
(完整word版)五年级上册小数简便运算总结,推荐文档小数简便运算(一)类型一:小数加减法【加法交换律的应用。
一般情况下,先观察数字,可以把有些数字先加起来,凑成整数,然后再和其他数字相加】例:1.64+5.7+8.36+4.3 =(1.64+8.36)+(5.7+4.3) =10+10 =20 3.2+0.36+4.8+1.64 0.456+6.22+3.786.9+4.8+3.1 1.29+3.7+2.71+6.30.398+0.36+3.64 4.02+5.4+0.983.82+2.9+0.18+9.1 1.27+3.9+0.73+16.11.57+0.245+7.432.64+8.67+7.36+11.330.134+2.66+0.866 1.76+0.195+3.24(二)类型二:减法性质的应用【a-b-c=a-(b+c)】根据性质观察题目,把后两个数字加起来带上括号,先算括号里面的加法,一般情况下都能加成整数。
例:35.6-1.8-15.6-7.2=35.6-15.6-(1.8+7.2)=20-9=1123.4-0.8-13.4-7.2 15.02-6.8-1.028-2.45-1.55 13.75-(3.75+6.48) 15.89+(6.75-5.89) 12.7-(3.7+0.84) 73.8-1.64-13.8-5.36 7.14-0.53-2.47 5.17-1.8-3.2 66.86-8.66-1.34 36.8-3.9-6.1 【在加减混合运算的简便运算中,可以先观察题目,会发现有的可以交换位置,进过加减变成整数的加减。
】例:3.25+1.79-0.59+1.75 =3.25+1.75+(1.79-0.59)(交换数字位置,=5-1.2 符号不变,用1.79先减0.59,把3.25 =3.8 和1.75加起来。
得整数5,再减)1.23+3.4-0.23+6.6 7.5+4.9-6.5 7.85+2.34-0.85+4.66 13.35-4.68+2.65 9.6+4.8-3.6 5.27+2.86-0.66+1.63 3.68+7.56-2.68 47.8-7.45+8.8 小数乘法简便运算乘法交换律的应用(首先观察题目,题目中会出现,25,2.5,0.25等和25相关的数字,这些数字要和4相关的数字结合。
5年级上册数学简便运算
5年级上册数学简便运算一、加法结合律与交换律1. 4.56 + 3.21 + 5.44-解析:运用加法交换律,先算4.56 + 5.44 = 10,再加上3.21,结果为13.21。
2. 23.5 + 18.7 + 6.5-解析:先算23.5 + 6.5 = 30,再加上18.7,结果为48.7。
3. 12.8 + 34.7 + 7.2-解析:12.8 与7.2 结合先算,12.8 + 7.2 = 20,再加上34.7,结果为54.7。
二、乘法结合律与交换律1. 2.5×4.8×0.4-解析:2.5 与0.4 结合先算,2.5×0.4 = 1,再乘以4.8,结果为4.8。
2. 1.25×3.2×8-解析:1.25 与8 结合先算,1.25×8 = 10,再乘以3.2,结果为32。
3. 4.5×2.4×0.5-解析:4.5 与0.5 结合先算,4.5×0.5 = 2.25,再乘以2.4,结果为5.4。
三、乘法分配律1. 2.5×(40 + 4)-解析:根据乘法分配律,2.5×40 + 2.5×4 = 100 + 10 = 110。
2. 12.5×(8 + 0.8)-解析:12.5×8 + 12.5×0.8 = 100 + 10 = 110。
3. 3.6×(100 + 2)-解析:3.6×100 + 3.6×2 = 360 + 7.2 = 367.2。
四、减法的性质1. 56.8 - 12.5 - 7.5-解析:56.8 - (12.5 + 7.5) = 56.8 - 20 = 36.8。
2.45.7-8.9-1.1-解析:45.7 - (8.9 + 1.1) = 45.7 - 10 = 35.7。
2.45.7-8.9-2.3-解析:32.5 - (6.7 + 3.3) = 32.5 - 10 = 22.5。
级上册数学简便计算及答案
级上册数学简便计算及答案小学数学五年级上册简便计算68道题(含详细答案)3.29+0.73+2.27 3.29-0.73-2.27 7.5+2.5-7.5+2.57.325-3.29-3.3257.325-(5.325+1.7)7.325-(5.325-1.7) 3.29+0.73-2.29+2.27 3.29×0.25×4 0.125×8.80.25×0.280.125×3.2×2.5 35×10.2 0.25×4÷0.25×43.5×9.9 3.5×99+3.53.5×101-3.5 3.5×9.9+3.5×0.1 3.5×2.7+35×0.733.5×2.7-3.5×0.7 (32+5.6)÷0.8 3.5÷0.6-0.5÷0.64.9÷1.4 7÷0.25÷4 7÷0.1257.35÷(7.35×0.25) 7.35÷(7.35÷0.25)3.07-0.38-1.62 1.29+3.7+2.71+6.38-2.45-1.55 3.25+1.79-0.59+1.7523.4-0.8-13.4-7.2 0.32×4033.2+0.36+4.8+1.64 1.23+3.4-0.23+6.60.25×36 12.7-(3.7+0.84) 36.54-1.76-4.54 0.25×0.73×4 7.6×0.8+0.2×7.6 0.85×199 0.25×8.5×41.28×8.6+0.72×8.612.5×0.96×0.810.4-9.6×0.350.8×(4.3×1.25) 3.12+3.12×99 28.6×101-28.6(4.23+6.17)×0.8 0.86×15.7-0.86×14.7 2.4×10214-7.32-2.68 2.64+8.67+7.36+11.33 2.31×1.2×0.5(2.5-0.25)×0.49.16×1.5-0.5×9.163.6-3.6×0.54.5÷1.8 930÷0.6÷563.4÷2.5÷0.4 4.25÷2.5×9.9+0.173.9÷(1.3×5)(7.7+1.54)÷0.72.5×2.4 2.7÷450.35×1.25×2×0.8 32.4×0.9+0.1×32.415÷0.25 15÷(0.15×0.4)小学数学五年级上册简便计算练习(答案卷)一、归类练习:3.29+0.73+2.27 3.29-0.73-2.27 7.5+2.5-7.5+2.5=3.29+(0.73+2.27)=3.29-(0.73+2.27) =(7.5-7.5)+(2.5+2.5)=3.29+3 =3.29-3 =0+5=6.29 =0.29 =5(加法结合律)(减法的性质)(同级运算交换)7.325-3.29-3.325 7.325-(5.325+1.7) 7.325-(5.325-1.7)=7.325-3.325-3.29 =7.325-5.325-1.7 =7.325-5.325+1.7=4-3.29 =2-1.7 =2+1.7(减法交换)(减法的性质)(前面减号,脱括号变符号)3.29+0.73-2.29+2.27 3.29×0.25×4 0.125×8.8=(3.29-2.29)+(0.73+2.27) =3.29×(0.25×4)=0.125×8×1.1 =1+3 =3.29×1 =1×1.1=4 =3.29 =1.1(同级运算交换)(乘法结合律)(先拆数,乘法结合律)0.25×0.28 0.125×3.2×2.5 35×10.2=0.25×4×0.07 =(0.125×8)×(0.4×2.5)=35×(10+0.2)=1×0.07 =1×1 =35×10+35×0.2=0.07 =1 =350+7(先拆数,乘法结合律)(拆数,乘法结合律) =357(拆数,乘法分配律)0.25×4÷0.25×4 3.5×9.9 3.5×99+3.5=(0.25÷0.25)×(4×4)=3.5×(10-0.1)=3.5×(99+1)=1×16 =3.5×10-3.5×0.1 =3.5×100=16 =35-0.35 =350(同级运算交换) =34.65 (乘法分配律)(拆数,乘法分配律)3.5×101-3.5 3.5×9.9+3.5×0.1★ 3.5×2.7+35×0.73=3.5×(101-1) =3.5×(9.9+0.1)=3.5×2.7+3.5×7.3=3.5×100 =3.5×10 =3.5×(2.7+7.3)(乘法分配律)(乘法分配律) =35(先利用积不变的规律转化,然后再用乘法分配律)3.5×2.7-3.5×0.7★ (32+5.6)÷0.8★ 3.5÷0.6-0.5÷0.6 =3.5×(2.7-0.7) =32÷0.8+5.6÷0.8=(3.5-0.5)÷0.6=3.5×2 =40+7 =3÷0.6=7 =47 =5(乘法分配律)(后2题类似分配律,但只适用于(a+b)÷c和(a-b)÷c,而a÷(b+c)和a÷(b-c)不能用。
小学数学五年级上册简便计算68道题(含答案)
小学数学五年级上册简便计算68道题(含详细答案)3.29+0.73+2.27 3.29-0.73-2.27 7.5+2.5-7.5+2.57.325-3.29-3.325 7.325-(5.325+1.7) 7.325-(5.325-1.7)3.29+0.73-2.29+2.27 3.29×0.25×4 0.125×8.83.2×2.5 35×10.2 0.25×4÷0.25×4 0.25×0.28 0.125×3.5×9.9 3.5×99+3.53.5×101-3.5 3.5×9.9+3.5×0.1 3.5×2.7+35×0.733.5×2.7-3.5×0.7 (32+5.6)÷0.8 3.5÷0.6-0.5÷0.64.9÷1.4 7÷0.25÷4 7÷0.1257.35÷(7.35×0.25) 7.35÷(7.35÷0.25)3.07-0.38-1.62 1.29+3.7+2.71+6.38-2.45-1.55 3.25+1.79-0.59+1.7523.4-0.8-13.4-7.2 0.32×4033.2+0.36+4.8+1.64 1.23+3.4-0.23+6.6 0.25×3612.7-(3.7+0.84)36.54-1.76-4.54 0.25×0.73×47.6×0.8+0.2×7.6 0.85×199 0.25×8.5×40.96×0.8 10.4-9.6×0.351.28×8.6+0.72×8.6 12.5×0.8×(4.3×1.25) 3.12+3.12×99 28.6×101-28.6(4.23+6.17)×0.8 0.86×15.7-0.86×14.7 2.4×10214-7.32-2.68 2.64+8.67+7.36+11.33 2.31×1.2×0.5 (2.5-0.25)×0.4 9.16×1.5-0.5×9.163.6-3.6×0.54.5÷1.8 930÷0.6÷563.4÷2.5÷0.4 4.25÷2.5×9.9+0.173.9÷(1.3×5)(7.7+1.54)÷0.72.5×2.4 2.7÷450.35×1.25×2×0.8 32.4×0.9+0.1×32.415÷0.25 15÷(0.15×0.4)小学数学五年级上册简便计算练习(答案卷)一、归类练习:3.29+0.73+2.27 3.29-0.73-2.27 7.5+2.5-7.5+2.5=3.29+(0.73+2.27)=3.29-(0.73+2.27) =(7.5-7.5)+(2.5+2.5)=3.29+3 =3.29-3 =0+5=6.29 =0.29 =5(加法结合律)(减法的性质)(同级运算交换)7.325-3.29-3.325 7.325-(5.325+1.7) 7.325-(5.325-1.7)=7.325-3.325-3.29 =7.325-5.325-1.7 =7.325-5.325+1.7=4-3.29 =2-1.7 =2+1.7=0.71 =0.3 =3.7(减法交换)(减法的性质)(前面减号,脱括号变符号)3.29+0.73-2.29+2.27 3.29×0.25×4 0.125×8.8=(3.29-2.29)+(0.73+2.27) =3.29×(0.25×4)=0.125×8×1.1=1+3 =3.29×1 =1×1.1=4 =3.29 =1.1(同级运算交换)(乘法结合律)(先拆数,乘法结合律)0.25×0.28 0.125×3.2×2.5 35×10.2=0.25×4×0.07 =(0.125×8)×(0.4×2.5)=35×(10+0.2)=1×0.07 =1×1 =35×10+35×0.2=0.07 =1 =350+7(先拆数,乘法结合律)(拆数,乘法结合律) =357(拆数,乘法分配律)0.25×4÷0.25×4 3.5×9.9 3.5×99+3.5=(0.25÷0.25)×(4×4)=3.5×(10-0.1)=3.5×(99+1)=1×16 =3.5×10-3.5×0.1 =3.5×100=16 =35-0.35 =350(同级运算交换) =34.65 (乘法分配律)(拆数,乘法分配律)3.5×101-3.5 3.5×9.9+3.5×0.1 ★ 3.5×2.7+35×0.73=3.5×(101-1) =3.5×(9.9+0.1)=3.5×2.7+3.5×7.3=3.5×100 =3.5×10 =3.5×(2.7+7.3)=350 =35 =3.5×10(乘法分配律)(乘法分配律) =35(先利用积不变的规律转化,然后再用乘法分配律)3.5×2.7-3.5×0.7 ★ (32+5.6)÷0.8 ★ 3.5÷0.6-0.5÷0.6=3.5×(2.7-0.7) =32÷0.8+5.6÷0.8 =(3.5-0.5)÷0.6=3.5×2 =40+7 =3÷0.6=7 =47 =5(乘法分配律)(后2题类似分配律,但只适用于(a+b)÷c和(a-b)÷c,而a÷(b+c)和a÷(b-c)不能用。
小学数学五年级上册简便计算68道题(含详细答案)
小学数学五年级上册简便计算68道题(含详细答案)3.29+0.73+2.273.29-0.73-2.277.5+2.5-7.5+2.57.325-3.29-3.3257.325-(5.325+1.7)7.325-(5.325-1.7)3.29+0.73-2.29+2.273.29×0.25×40.125×8.8零点二五×0.280.125×三点二二×二点五三五×10.20.25×4÷0.25×四3.5×9.93.5×99+3.5三点五×101-3.53.5×9.9+3.5×0.13.5×2.7+35×零点七三1三点五×2.7-3.5×0.7(32+5.6)÷0.83.5÷0.6-0.5÷0.64.9÷1.47÷0.25÷47÷0.1257.35÷(7.35 × 0.25)3.07-0.38-1.628-2.45-1.5523.4-0.8-13.4-7.27.35÷(7.35÷0.25)1.29+3.7+2.71+6.33.25+1.79-0.59+1.750.32×肆佰叁拾二元3.2+0.36+4.8+1.641.23+3.4-0.23+6.60.25×3612.7-(3.7+0.84)36.54-1.76-4.540.25×零点七三×四7.6×0.8+0.2×7.61.28×8.6+0.72×8.60.8×(4.3×1.25)3.12(4.23+6.17)×零点八14-7.32-2.68零点八五×一千九百九十九点二五×八点五×四百一十二点五×零点九六×0.810.4-9.6×0.35+3.12×九千九百二十八点六×101-28.60.86×15.7-0.86×14.72×一百零二2.64+8.67+7.36+11.332.31×1.2×0.5三(2.5-0.25)×0.49.16×1.5-0.5×9.163.6-3.6 × 0.54.5÷1.8930÷0.6÷563.4÷2.5÷0.44.25÷2.5×9.9+0.173.9÷(1.3 × 5)(7.7+1.54)÷0.72.5×2.42.7÷45零点三五×一点二五×二×0.832.4×0.9+0.1×三十二点四15÷0.2515÷(0.15×0.4)四小学数学五年级上册简便计算练习(答案卷)一、分类工作:3.29+0.73+2.273.29-0.73-2.277.5+2.5-7.5+2.5=3.29+(0.73+2.27)=3.29-(0.73+2.27)=(7.5-7.5)+(2.5+2.5)=3.29+3=3.29-3=0+5=6.29=0.29=5(加法组合定律)(减法性质)(同级运算交换)7.325-3.29-3.3257.325-(5.325+1.7)7.325-(5.325-1.7)=7.325-3.325-3.29=7.325-5.325-1.7=7.325-5.325+1.7=4-3.29=2-1.7=2+1.7=0.71=0.3=3.7(减法交换)(减法的本质)(前面有减号,从括号中变成一个符号)3.29+0.73-2.29+2.273.29×0.25×40.125×8.8=(3.29-2.29)+(0.73+2.27)=3.29×(0.25×4)=0.125×8×1.1=1+3=3.29×1=1×1.1=4=3.29=1.1(同级运算交换)(乘法组合法则)(第一次分割数,乘法组合法则)0.25×0.280.125×3.2×2.535×10.2=0.25×4×0.07=(0.125×8)×(0.4×2.5)=35×(10+0.2)=1×0.07=1×1=35×10+35×0.2=0.07=1=350+7(先拆数,乘法结合律)(拆数,乘法结合律)=357(拆数,乘法分配律)零点二五×4÷0.25×四十三点五×9.93.5×99+3.5=(0.25÷0.25)×(4×4)=3.5×(10-0.1)=3.5×(99+1)=1×16=3.5×10-3.5×0.1=3.5×100=16=35-0.35=350(同级运算交换)=34.65(乘法分配律)(分裂数,乘法分布定律)3.5×101-3.53.5×9.9+3.5×0.1★3.5×2.7+35×0.73=3.5×(101-1)=3.5×(9.9+0.1)=3.5×2.7+3.5×7.3=3.5×100=3.5×10=3.5×(2.7+7.3)=350=35=3.5×10(乘法分配律)(乘法分配律)=35(首先使用乘积不变性定律进行变换,然后再用乘法分配律)五。
小学数学五年级上册简便计算68道题(含详细规范标准答案)
小学数学五年级上册简便计算68道题(含详细规范标准答案)一、加减法简便计算1. 123 + 456 = 5792. 789 321 = 4683. 678 + 123 456 = 3454. 456 + 789 123 = 11225. 987 + 654 321 = 13206. 789 + 456 123 = 11227. 654 + 321 987 = 3128. 321 + 987 654 = 6549. 123 + 456 + 789 = 136810. 456 + 789 + 123 = 1368二、乘除法简便计算11. 7 × 8 = 5612. 9 ÷ 3 = 313. 12 × 13 = 15614. 15 ÷ 5 = 315. 18 × 19 = 34216. 21 ÷ 7 = 317. 24 × 25 = 60018. 27 ÷ 9 = 319. 30 × 31 = 93020. 33 ÷ 11 = 3三、混合运算简便计算21. 12 + 7 × 8 = 6822. 9 ÷ 3 + 6 = 723. 12 × 13 45 = 14124. 15 ÷ 5 + 8 = 725. 18 × 19 + 21 = 35726. 21 ÷ 7 4 = 127. 24 × 25 12 = 58828. 27 ÷ 9 + 3 = 629. 30 × 31 15 = 91530. 33 ÷ 11 2 = 1四、分数简便计算31. 1/2 + 1/3 = 5/632. 2/3 ÷ 1/4 = 8/333. 3/4 + 1/2 = 5/434. 4/5 ÷ 1/2 = 8/535. 5/6 + 1/3 = 7/636. 6/7 ÷ 1/4 = 24/737. 7/8 + 1/2 = 11/838. 8/9 ÷ 1/3 = 839. 9/10 + 1/5 = 13/1040. 10/11 ÷ 1/2 = 20/11五、小数简便计算41. 0.5 + 0.3 = 0.842. 0.6 ÷ 0.2 = 343. 0.7 × 0.8 = 0.5644. 0.4 ÷ 0.4 = 145. 0.9 + 0.1 = 146. 0.8 ÷ 0.2 = 447. 0.7 × 0.9 = 0.6348. 0.6 ÷ 0.3 = 249. 0.5 + 0.2 = 0.750. 0.4 ÷ 0.2 = 2六、百分数简便计算51. 20% + 30% = 50%52. 40% ÷ 20% = 253. 50% × 80% = 40%54. 25% + 75% = 100%55. 60% ÷ 30% = 256. 70% × 50% = 35%57. 80% + 20% = 100%58. 90% ÷ 10% = 959. 55% × 45% = 24.75%60. 65% + 35% = 100%七、方程简便计算61. 2x + 3 = 7,解得 x = 262. 3x 4 = 5,解得 x = 363. 4x + 5 = 9,解得 x = 164. 5x 6 = 4,解得 x = 265. 6x + 7 = 13,解得 x = 166. 7x 8 = 9,解得 x = 367. 8x + 9 = 17,解得 x = 168. 9x 10 = 11,解得 x = 3八、应用题简便计算69. 小华有10个苹果,小明有15个苹果,他们一共有多少个苹果?解:10 + 15 = 25个苹果。