小学数学五年级培优作业
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发布时间:2022-04-29 03:50
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共5个回答
热心网友
时间:2023-10-09 20:14
1/6+1/12+1/20+1/30+1/42+1/56+1/72
=1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9
=1/2-1/9
=7/18
热心网友
时间:2023-10-09 20:14
1/6 = 1/2 - 1/3
1/12 = 1/3 - 1/4
1/20 = 1/4 -1/5
1/30 = 1/5 -1/6
1/42 = 1/6 - 1/7
1/56 = 1/7 - 1/8
1/72 = 1/8 - 1/9
1/6+1/12+1/20+1/30+1/42+1/56+1/72
=(1/2 - 1/3) + (1/3 - 1/4 )+ (1/4 -1/5 )+ (1/5 -1/6) + (1/6 - 1/7) + (1/7 - 1/8) +(1/8 - 1/9)
=1/2 - 1/9
=7/18
热心网友
时间:2023-10-09 20:15
根据规律得:
1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9
=1/2-1/9
=7/18
热心网友
时间:2023-10-09 20:15
1/6+1/12+1/20+1/30+1/42+1/56+1/72
=(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+(1/5-1/6)+(1/6-1/7)+(1/7-1/8)+(1/8-1/9)
=1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9
=1/2-1/9
=7/18
热心网友
时间:2023-10-09 20:16
原式=(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+(1/5-1/6)
+(1/6-1/7)+(1/7-1/8)+(1/8-1/9)
=1/2-1/9
=4/9
热心网友
时间:2023-10-09 20:14
1/6+1/12+1/20+1/30+1/42+1/56+1/72
=1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9
=1/2-1/9
=7/18
热心网友
时间:2023-10-09 20:14
1/6 = 1/2 - 1/3
1/12 = 1/3 - 1/4
1/20 = 1/4 -1/5
1/30 = 1/5 -1/6
1/42 = 1/6 - 1/7
1/56 = 1/7 - 1/8
1/72 = 1/8 - 1/9
1/6+1/12+1/20+1/30+1/42+1/56+1/72
=(1/2 - 1/3) + (1/3 - 1/4 )+ (1/4 -1/5 )+ (1/5 -1/6) + (1/6 - 1/7) + (1/7 - 1/8) +(1/8 - 1/9)
=1/2 - 1/9
=7/18
热心网友
时间:2023-10-09 20:15
根据规律得:
1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9
=1/2-1/9
=7/18
热心网友
时间:2023-10-09 20:15
1/6+1/12+1/20+1/30+1/42+1/56+1/72
=(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+(1/5-1/6)+(1/6-1/7)+(1/7-1/8)+(1/8-1/9)
=1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9
=1/2-1/9
=7/18
热心网友
时间:2023-10-09 20:16
原式=(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+(1/5-1/6)
+(1/6-1/7)+(1/7-1/8)+(1/8-1/9)
=1/2-1/9
=4/9
热心网友
时间:2023-10-09 20:14
1/6+1/12+1/20+1/30+1/42+1/56+1/72
=1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9
=1/2-1/9
=7/18
热心网友
时间:2023-10-09 20:14
1/6 = 1/2 - 1/3
1/12 = 1/3 - 1/4
1/20 = 1/4 -1/5
1/30 = 1/5 -1/6
1/42 = 1/6 - 1/7
1/56 = 1/7 - 1/8
1/72 = 1/8 - 1/9
1/6+1/12+1/20+1/30+1/42+1/56+1/72
=(1/2 - 1/3) + (1/3 - 1/4 )+ (1/4 -1/5 )+ (1/5 -1/6) + (1/6 - 1/7) + (1/7 - 1/8) +(1/8 - 1/9)
=1/2 - 1/9
=7/18
热心网友
时间:2023-10-09 20:15
根据规律得:
1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9
=1/2-1/9
=7/18
热心网友
时间:2023-10-09 20:15
1/6+1/12+1/20+1/30+1/42+1/56+1/72
=(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+(1/5-1/6)+(1/6-1/7)+(1/7-1/8)+(1/8-1/9)
=1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9
=1/2-1/9
=7/18
热心网友
时间:2023-10-09 20:16
原式=(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+(1/5-1/6)
+(1/6-1/7)+(1/7-1/8)+(1/8-1/9)
=1/2-1/9
=4/9