有一題數學題不明白~

easiest method: count them out
you were just too lazy to do it right? I'll list them out for you

45A|75B|105D
46B|76A|106C
47C|77A|107B
48D|78B|108A
49D|79C|109A
50C|80D|110B
51B|81D|111C
52A|82C|112D
53A|83B|113D
54B|84A|114C
55C|85A|115B
56D|86B|116A
57D|87C|117A
58C|88D|118B
59B|89D|119C
60A|90C|120D
61A|91B|121D
62B|92A|122C
63C|93A|123B
64D|94B|124A
65D|95C|125A
66C|96D|126B
67B|97D|127C
68A|98C|128D
69A|99B|129D
70B|100A|130C
71C|101A|131B
72D|102B|132A
73D|103C|133A
74C|104D|134B
||135C
||136D
||137D

you'll be in class D

2007-07-11 16:10:01 補充：
to do it the MATHEMATICAL way...there are 8 letters in a group: A B C D D B C A start counting at 45there are 137 - 44 = 93 numbers to count93 / 8 = 11 with 5 leftcount 5 into the pattern:1A 2B 3C 4D 5Dtherefore you'll be in class D

先理解一下題目中, 分班的名次是以 8 名為一個循環.
所以我們可以由 8 為一循環的手法著手:
此循環為:
1 = A
2 = B
3 = C
4 = D
5 = D
6 = C
7 = B
8 = A
然後, 45 為第一, 所以可以理解為:
45 - 44 = 1
即把名次先減去 44, 再將差額除 8, 將餘數與以上的表核對.
如此: 137 名將會是:

減去 44 = 93
93 除 8 餘數 = 5
核對以上的表, 便可知應被編入 D 班了.

一句講晒------D

點解你地分班咁得意嘅?

每8個就回到A班,137/8=17...1
所以是A班

我答的就是上面幾位答的，唔洗答

將137-45=92,將92除4=23,因為ABCD DCBA係2個組合,SO ,將23除2=12餘1,因為ABCD排先,SO 23組合係ABCD 姐係你係D班

2007-07-11 15:48:02 補充：
都唔明點解上面D人計都咁複雜,我呢個簡單D,(唔好罵我呀),嗚嗚除4係因為4個英文字一組,講少左

2007-07-11 15:54:17 補充：
講少左23組係ABCD,+1姐係+多一個,姐係D

2007-07-12 14:07:39 補充：
23除2係11餘1,SOR打錯左

The reminder of the series is

1=A, 2=B, 3=C,4=D, 5=D, 6=C, 7=B, 0=A.

For example

no. 50 is C.

(50-44)/8=6/8=0.....6
That mean after 0 cycle, reminder is 6=C.

so (137-44)/8=93/8=11.....5
reminder is 5=D

A to B to C to D to D to C to B to A to A to B to C to D 為一組合, 你係137名, 咁即係包括左17個組合再+1, 所以你係A班.

137=17x8+1