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#1 2013-01-22 04:13:22
- cooljackiec
- Full Member
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probability and counting??
How many 20-digit numbers are such that the sum of their digits is even?
I see you have graph paper.
You must be plotting something
#3 2013-01-22 08:25:37
- cooljackiec
- Full Member
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Re: probability and counting??
That doesn't help, I knew that just that i keep losing count.
I see you have graph paper.
You must be plotting something
#4 2013-01-22 12:24:26
- bobbym
- Administrator
Online
Re: probability and counting??
Hi;
You do not have to do much counting. Spot the pattern works well here.
I am getting 4.5 x 10 ^19 numbers.
In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.
#5 2013-01-23 11:02:13
- cooljackiec
- Full Member
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Re: probability and counting??
Thank you
I see you have graph paper.
You must be plotting something