“数字是不会骗人的,”老师说:“一座房子,如果一个人要花上十二天盖好,十二个人就只要一天。二百八十八人只要一小时就够了。”一个学生接着说:“一万七千二百八十人只要一分钟,一百零三万六千八百人只要一秒钟。此外,如果一艘轮船横渡大西洋要六天,六艘轮船只要一天就够了。四杯25度的水加在一起就变开水了!数字是不会骗人的!”
1.25x6.5x0.8
=1.25x0.8x6.5
=1x6.5
=6.5
50道简便运算题:
30×20= 400÷4= 350-80= 160+70=
18-64÷8= 42÷6+20= 40-5×7= 80+60÷3=
41+18÷2= 75-11×5= 2+7-29= 尺手中5600÷80=
25×16= 120×25= 36×11= 1025÷25=
336+70= 25×9×4= 200-33×3= 3020-1010=
5.48+7.56= 3.9+6.1= 4.2+2.8= 3.2×4=
95.7-59= 8.6×9= 55÷5.5= 24×125=
52÷32×8= 70÷(14×1)= 63×58-63×39= 92×99+92=
855-422+222= 58×299= 52×69= 80÷(5×4)=
20×3×25= 16×6+16×4= 1400-(98+81)= 6×9×5=
45+15×6= 250÷5×8= 6×5÷2×4= 30×3+8=
400÷4+20×5= 10+12÷3+20= (80÷20)÷4= 70+(10×5)=
360÷40= 40×20=
50道混合运算:
125×(8+0.8+0.08) 35 ÷〔78-(25+38)〕 3.35×6.4×2+6.7×3.6
18.7-3.375-6.625 25×1.25×32 1.28+9.8+7.72+10.2
12 ×1951 +12×2049 0.64×25×7.8+2.2 2÷2.5+2.5÷2
194-64.8÷1.8×0.9 36.72÷4.25×9.9 5180-705×6
24÷2.4-2.5×0.8 671×15-974 469×12+1492
405×(3213-3189) 12*(1/2+2/3+5/6) 1.25×17.6+36.1÷0.8+2.63×12.5
58870÷(105+20×2) [37.85-(7.85+6.4)] ×30 [192-(54+38)]×67
[(7.1-5.6)×0.9-1.15]÷2.5 [60-(9.5+28.9)]÷0.18 20×[(2.44-1.8)÷0.4+0.15]
0.8×[(10-6.76)÷1.2]
35.95÷(64-45) 36.178-145÷5×6+42 420+580-64×21÷28
37.812-700÷(9+31×11) (136+64)×(65-345÷23) 38.85+14×(14+208÷26)
(284+16)×(512-8208÷18) 5.38+7.85-5.37
7.2÷0.8-1.2×5 6-1.19×3-0.43
6.5×(4.8-1.2×4) 0.68×1.9+0.32×1.9
10.15-10.75×0.4-5.7 5.8×(3.87-0.13)薯迟+4.2×3.74
32.52-(6+9.728÷3.2)×2.5 [(7.1-5.6)×0.9-1.15] ÷2.5
5.4÷[2.6×(3.7-2.9)陵山+0.62] 12×6÷(12-7.2)-6
50+160÷40 ( 58+370)÷(64-45)
120-144÷18+35 347+45×2-4160÷52
(58+37)÷(64-9×5) 95÷(64-45)
178-145÷5×6+42 420+580-64×21÷28