document.write( "Question 89327: I need to find the classic probability of rolling a 1 (or any number) out of 8 dice. I'm not looking for the total face value, just the frequency of rolling a 1 out of 8 dice. So, \"What is the probability that you will roll a single 1 out of 8 dice?\", \"What is the probability you will roll two 1s out of 8 dice?\" and so on.\r
\n" ); document.write( "\n" ); document.write( "What I have tried:
\n" ); document.write( "(when rolling no 1s out of 8 dice) I used: \"%28%281%2F6%29%5E0%29%2A%28%285%2F6%29%5E8%29\"
\n" ); document.write( "(when rolling a single 1 out of 8 dice) I used: \"%28%281%2F6%29%5E1%29%2A%28%285%2F6%29%5E7%29\".
\n" ); document.write( "(when rolling two 1s out of 8 dice) I used: \"%28%281%2F6%29%5E2%29%2A%28%285%2F6%29%5E6%29\" \r
\n" ); document.write( "\n" ); document.write( "Alternately, I tried the same thing without using powers in my formulas.... but this didn't seem to help. \r
\n" ); document.write( "\n" ); document.write( "My total probability for the set did not add up to 1, so I think I must be missing a step? Please help! \n" ); document.write( "
Algebra.Com's Answer #64889 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
Your numbers have taken care of the independent nature of the event but
\n" ); document.write( "not the mutually exclusive nature of the event.
\n" ); document.write( "For example getting one \"1\" on the 8 dice is (1/6)^1(5/6)^7 takes care
\n" ); document.write( "of getting the \"1\" on the 1st dice; but getting the one on the
\n" ); document.write( "2nd dice is a mututally exclusive event and has the same probability,
\n" ); document.write( "and the same for a \"1\" on the 3rd dice etc.
\n" ); document.write( "So the probability of getting one \"1\" is 8C1(1/6)(5/6)^7 = 8(1/6)(5/6)^7
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\n" ); document.write( "Similarly the probability of getting two \"1's\" is 8C2(1/6)^2(5/6)^6=
\n" ); document.write( "28(1/6)^2(5/6)^6
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\n" ); document.write( "If you continue this to 8C8(1/6)^8(5/6)^0 and add up the terms they will
\n" ); document.write( "add up to one.
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \r
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