1.甲数比乙数大10%,乙数比丙数少10%,甲丙两数相比较( ).2.计算1/2001+3/2001+5/2001+``````+1999/2001(要过程)3.简算:38.4*187-15.4*384+3.3*164.简算:5727*1479-615/864+5726*14795.简算:7/12-9/20+11/30-13/42+15/56-17/
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![1.甲数比乙数大10%,乙数比丙数少10%,甲丙两数相比较( ).2.计算1/2001+3/2001+5/2001+``````+1999/2001(要过程)3.简算:38.4*187-15.4*384+3.3*164.简算:5727*1479-615/864+5726*14795.简算:7/12-9/20+11/30-13/42+15/56-17/](/uploads/image/z/6823757-29-7.jpg?t=1.%E7%94%B2%E6%95%B0%E6%AF%94%E4%B9%99%E6%95%B0%E5%A4%A710%25%2C%E4%B9%99%E6%95%B0%E6%AF%94%E4%B8%99%E6%95%B0%E5%B0%9110%25%2C%E7%94%B2%E4%B8%99%E4%B8%A4%E6%95%B0%E7%9B%B8%E6%AF%94%E8%BE%83%EF%BC%88+%EF%BC%89.2.%E8%AE%A1%E7%AE%971%2F2001%2B3%2F2001%2B5%2F2001%2B%60%60%60%60%60%60%2B1999%2F2001%EF%BC%88%E8%A6%81%E8%BF%87%E7%A8%8B%EF%BC%893.%E7%AE%80%E7%AE%97%EF%BC%9A38.4%2A187-15.4%2A384%2B3.3%2A164.%E7%AE%80%E7%AE%97%EF%BC%9A5727%2A1479-615%2F864%2B5726%2A14795.%E7%AE%80%E7%AE%97%EF%BC%9A7%2F12-9%2F20%2B11%2F30-13%2F42%2B15%2F56-17%2F)
1.甲数比乙数大10%,乙数比丙数少10%,甲丙两数相比较( ).2.计算1/2001+3/2001+5/2001+``````+1999/2001(要过程)3.简算:38.4*187-15.4*384+3.3*164.简算:5727*1479-615/864+5726*14795.简算:7/12-9/20+11/30-13/42+15/56-17/
1.甲数比乙数大10%,乙数比丙数少10%,甲丙两数相比较( ).
2.计算1/2001+3/2001+5/2001+``````+1999/2001(要过程)
3.简算:38.4*187-15.4*384+3.3*16
4.简算:5727*1479-615/864+5726*1479
5.简算:7/12-9/20+11/30-13/42+15/56-17/72+19/90
1.甲数比乙数大10%,乙数比丙数少10%,甲丙两数相比较( ).2.计算1/2001+3/2001+5/2001+``````+1999/2001(要过程)3.简算:38.4*187-15.4*384+3.3*164.简算:5727*1479-615/864+5726*14795.简算:7/12-9/20+11/30-13/42+15/56-17/
1、假设丙是100,则
乙是100×(1-10%)=90
甲是90×(1+10%)=99
甲
1、假设丙是100,则
乙是100×(1-10%)=90
甲是90×(1+10%)=99
甲<丙或甲比丙少(100-99)÷100=1%
2、1/2001+3/2001+5/2001+``````+1999/2001
=(1+3+5+7+...+1999)/2001
=(1+1999)×1000÷2/2001
=1000000/2001
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1、假设丙是100,则
乙是100×(1-10%)=90
甲是90×(1+10%)=99
甲<丙或甲比丙少(100-99)÷100=1%
2、1/2001+3/2001+5/2001+``````+1999/2001
=(1+3+5+7+...+1999)/2001
=(1+1999)×1000÷2/2001
=1000000/2001
=499又1501/2001
3、38.4*187-15.4*384+3.3*16
=384×18.7-15.4×384+3.3×16
=384×(18.7-15.4)+3.3×16
=3.3×(384+16)
=1320
4、5727*1479-615/864+5726*1479
=(5726+1)×1479-615/864+5726×1479
=5726×1479+1479-615/864+5726×1479
=5726×1479+864/864+5726×1479
=1
5、7/12-9/20+11/30-13/42+15/56-17/72+19/90
=(1/3+1/4)-(1/4+1/5)+(1/5+1/6)-(1/6+1/7)+(1/7+1/8)-(1/8+1/9)+(1/9+1/10)
=1/3+1/4-1/4-1/5+1/5+1/6-1/6-1/7+1/7+1/8-1/8-1/9+1/9+1/10
=1/3+1/10
=13/30
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设甲=x,则乙=10x/11,丙=100x/99
丙-甲=x/99
丙比甲大1/99
(1+3+5+…+1999)/2001=[(1+2+3+…+2000)-1000]/2001*2=[(1+2000)*2000/2-1000]/2001*2=1000000/2001
384*18.7-15.4*387+3.3*16=3.3*384+3.3*16=3.3*400=1...
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设甲=x,则乙=10x/11,丙=100x/99
丙-甲=x/99
丙比甲大1/99
(1+3+5+…+1999)/2001=[(1+2+3+…+2000)-1000]/2001*2=[(1+2000)*2000/2-1000]/2001*2=1000000/2001
384*18.7-15.4*387+3.3*16=3.3*384+3.3*16=3.3*400=1320
(5727*1479-615)/(864+5726*1479)=(5726*1479+1479-864)/(864+5726*1479)=1
(3+4)/3*4-(4+5)/4*5+(5+6)/5*6-(6+7)/6*7+(7+8)7*8-(8+9)/8*9+(9+10)/9*10=1/3+1/4-1/4-1/5+1/5+1/6-1/6-1/7+1/7+1/8-1/8-1/9+1/9+1/10=1/3+1/10=13/30
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