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连问两次.1.{(7又1/13+2.4÷6又2/5)+2又5/8}x52.{(10.75-4又11/12)x2又7/11

来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/05/14 18:53:35
连问两次.
1.{(7又1/13+2.4÷6又2/5)+2又5/8}x5
2.{(10.75-4又11/12)x2又7/11}÷{(1.125+1/12)÷(2.25÷10又10/11)}
3.1/(4x7)+1/(7x10).+1/(100x103)
4.1-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90
5.(46-1/7)x1/8+(43-1/7)x1/8+(41-1/7)x1/8+.+(1-1/7)x1/8
6.1+3又1/6+5又1/12+7又1/20+9又1/30+11又1/42+13又1/56+15又1/72+17又1/90
7.9999x2222+3333x3334
8.(0.25+1又5/18÷7又2/3)÷(4又1/2-0.925)
等待中.
1.{(7又1/13+2.4÷6又2/5)+2又5/8}x5
={92/13+24/10÷32/5)+21/8}x5
={92/13+24/10x5/32)+21/8}x5
={92/13+3/8+21/8}x5
={92/13+4}x5
={92/13+52/13}x5
=(144/13)x5
=720/13
=55又5/13.
2.{(10.75-4又11/12)x2又7/11}÷{(1.125+1/12)÷(2.25÷10又10/11)}
={(43/4-59/12)x29/11}÷{(9/8+1/12)÷(9/4÷120/11)}
={(129/12-59/12)x29/11}÷{(27/24+2/24)÷(9/4x11/120)}
={61/12x29/11}÷{29/24÷99/480}
=(1769/132)÷{29/24x480/99}
=(1769/132)÷(580/99)
=(1769/132)x(99/580)
=2.2875.
3.由1/(4x7)=[(1/4)-(1/7)]/3
1/(7x10)=[(1/7)-(1/10)]/3
.
1/(100x103)=[(1/100)-(1/103)]/3
得1/(4x7)+1/(7x10).+1/(100x103)
=[(1/4)-(1/103)]/3
=33/413.
4.1-5/6+7/12-9/20+11/30-13/42+15/56-17/72+19/90
=1-5x(1/2-1/3)+7x(1/3-1/4)-9x(1/4-1/5)+11x(1/5-1/6)-13x(1/6-1/7)+15x(1/7-1/8)-17x(1/8-1/9)+19x(1/9-1/10)
=-4.
5.(46-1/7)x1/8+(43-1/7)x1/8+(41-1/7)x1/8+.+(1-1/7)x1/8
=[46+43+41+...+1)-(1/7)*]/8
6.1+3又1/6+5又1/12+7又1/20+9又1/30+11又1/42+13又1/56+15又1/72+17又1/90
=(1+3+5+7+9+11+13+15+17)+[1/(2x3)+1/(3x4)+...+1/(9x10)]
=136+[(1/2-1/3)+(1/3-1/4)+.+(1/9-1/10)]
=136+[1/2-1/10]
=136又2/5.
7.9999x2222+3333x3334
=1111x9x1111x2+1111x3x(1111x3+1)
=1111x1111x(18+9)+1111x3
=1111x1111x30
=37029630.
8.(0.25+1又5/18÷7又2/3)÷(4又1/2-0.925)
=1又51/74.