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有谁会这题数学题吗??
If you take 7, then 17, and then 8 from me, you have 160. But if you take 6, then 17, then 8 from me, youhave 170.Finally, if you take 1, then 4, then 1 from me, you have 762. W ...
dadayz 发表于 2009-7-21 05:12 PM
a)if u take 7,then 17,then 8 from me,u hav 160.u take 32.
b)if u take 6,then 17,then 8 from me,u hav 170.u take 31.
c)if u take 1, then 4,then 1 from me,u hav 762.u take 6.
If *i = u*, thn
a)160+32=192
b)170+31=201
c)762+6=768
from arithmetic progression, we get the formulae:
Tn=a+(n-1)d.
Tn=768,a=192,n=unknown,d=201-192
=9
768=192+(n-1)(9)
768-192=(n-1)(9)
576=(n-1)9
64=n-1
n=65#
therefore, *i=u*
am i right? |
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