问题补充说明:50道简便计算题及答案?... 50道简便计算题及答案? 展开
(1)2.5*32*0.125
=(2.5类复务哥心入抓罗得处材*4)*(8*0.125)
=10*1
=10
(2)3.5-7+6.5
=3.5+6食鱼训节.5-7
=3
(3)1360问答.2×2.5+0言布失低名.8×2.5
=2.5(1.2+0.8)
=25
(4)8.9×1.25-0.9×1.25
=1.25(8.9-0.9)
=10
(5)12.5×7.4×0.8
=12.5×0.8×7.4
=74
(6)6.5×9.5+6.5×0绝员所肥杨所补建度改.5
=6.5×(9.5+0.5)
=6.5×10
=65
(7)0.35粮×1.6+0.35×3.4
=0.35*(1.6+3.4)
=0.35*5
=1.75
(考模谓家协8)6.72-3.28-1.72
=6.75-(3.28+1.72)
=6.75-5
=1.75
(9)0.45+6.37+4.55
=0.45+4.55+6.37
=5+6.37
=11.37
(10)28×12.5-12.5×20
=(28-20)*12.5
眼场器命按技纸言=8*12.5
=100
(11)23.65-(3.07+3.65)
=23.65-3.65-3.07
=20-3.07
=1建加一两春6.93
(12)(4+0.4×0.25)8×7×1.25
课劳课极当因机地刚=(4+1)*7呀革棉系布*10
=5*7*10
=350
(13)1.65×99+1.65
=1.65*(9底胡局持队段突9+1)
=1.65*100
=165
事求买(14)27.85-(7.85+3.4)
宜双转孔鲜军静奏已第友=27.85-7.85+3.4
=20+3.4
评蛋毫众小改=23.4
(15沿意因则输功普关修刘)48×1.25+50×1.2太历阶字阿官甚探5×0.2×8
7.8×9.9+0.78
=7.8*(9.9+0.1)
=7.8*10
=78
(16)4.8×46+4.8×54
=(46+54)*4.8
=10死鲜渐物0*4.8
=480
(17)673-327-173
=673-(327+173)
=673-500
=173
(18)4.44*2.5
=1.11*(4*2.5)
=1.11*10
=11.1
(19)3.5÷1.4
=(3.5÷0.7)÷(1.4÷0.7)
=5÷2
=2.5
(20)1+2+3+4+5......+99+100
=(1+99)+(2+98)+(3+97)+......+(49+51)+50
=(100÷2-1)*100+50
=4900+50
=4950⑴运用加法交换律进行简便计算。
0.88+5.6+0.121.78+3.5+0.225.6+2.08+14.4
=0.88+0.12+5.6=1.78+0.22+3.5=5.6+14.4+2.08
=1+5.6=2+3.5=20+2.08
=6.6=5.5=22.08
⑵运用加法结合律进行简便计算
2.3+(0.56+4.7)28.6+0.54+0.46+1.45.82+4.56+5.44
=(2.3+4.7)+0.56=(28.6+1.4)+(0.54+0.46)=5.82+(4.56+5.44)
=7+0.56=30+1=5.82+10
=7.56=31=15.82
⑶、运用乘法交换律进行唤斗简便计辩洞算。
25×0.37×0.47.5×0.39×46.5×1.1×41.25×3.9×0.8
=25×0.4×0.37=7.5×4×0.39=6.5×4×1.1=1.25×0.8×3.9
=10×0.37=携链枯30×0.39=26×1.1=1×3.9
=3.7=11.7=28.6=3.9
⑷、运用乘法结合律进行简便计算。
1.9×7.5×86.2×0.8×2.54.3×1.5×64.1×3.5×2
=1.9×(7.5×8)=6.2×(0.8×2.5)=4.3×(1.5×6)=4.1×(3.5×2)
=1.9×60=6.2×2=4.3×9=4.1×7
=114=12.4=38.7=28.7
⑸、运用乘法分配律的加法进行简算。
13.6×4.6+4.6×6.40.72×23+77×0.722.6×32+32×2.4
=(13.6+6.4)×4.6=(23+77)×0.72=(2.6+2.4)×32
=20×6.4=100×0.72=5×32
=128=72=160
⑹、运用乘法分配律的减法进行简算。
12×5.9-5.9×24.6×2.5-2.5×0.6101×9.7-9.7
=(12-2)×5.9=(4.6-0.6)×2.5=(101-1)×9.7
=(12-2)×5.9=(4.6-0.6)×2.5=(101-1)×9.7
=10×5.9=4×2.5=100×9.7
=59=10=970
⑺、运用减法的运算规律进行简便计算。
1.8-0.45-0.5554.4-4.6-5.435.6-0.13-0.47
=1.8-(0.45+0.55)=54.4-(4.6+5.4)=35.6-(0.13+0.47)
=1.8-1=54.4-10=35.6-0.6
=0.8=44.4=35
⑻、运用除法的运算规律进行简便计算。
4.5÷4÷7.514.8÷1.25÷818.5÷4÷1.255.4÷4÷0.45
=4.5÷(4×7.5)=14.8÷(1.25×8)=18.5÷(4×1.25)=5.4÷(4×0.45)
=4.5÷30=14.8÷10=18.5÷5=5.4÷0.18
=0.15=1.48=3.7=30
⑼综合运用各种运算定律进行简算。
2.54+2.46+0.44+0.5410.7×0.4-6.7×0.40.5×3.2×1.25
=(2.54+2.46)+(0.44+0.54)=(10.7-6.7)×0.4=(0.5×4)×(0.8×1.25)
=5+1=4×0.4=2×1
=6=1.6=2
89.7+5.8-9.7+4.299×0.38+0.38360÷(18×0.4)
=(89.7-9.7)+(5.8+4.2)=(99+1)×0.38=360÷18÷0.4
=80+10=100×0.38=20÷0.4
=90=38=50
4.8×12.52.5×1.6×12.53.2×102
=0.6×(8×12.5)=(2.5×0.2)×(8×12.5)=3.2×(100+2)
=0.6×100=0.5×100=3.2×100+3.2×2
=60=50=320+6.4
=326.4
标签:计算题,简便