document.write( "Question 72870: When two fair dice are rolled, the sum of the two dice can be any number from 2 through 12. What is the probability that this sum will be exactly a 7? Please show me how to solve this. \n" ); document.write( "
Algebra.Com's Answer #52097 by jmg(22)\"\" \"About 
You can put this solution on YOUR website!
This is hard to explain on here but I will try.\r
\n" ); document.write( "\n" ); document.write( "If you look at all the possible combinations:
\n" ); document.write( "1+1=2
\n" ); document.write( "1+2=3
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\n" ); document.write( "1+6=7\r
\n" ); document.write( "\n" ); document.write( "then go to the 2's, you have already used 1+ 2 so now start with
\n" ); document.write( "2+2=4
\n" ); document.write( "2+3=5
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\n" ); document.write( "2+5=7
\n" ); document.write( "2+6=8\r
\n" ); document.write( "\n" ); document.write( "then go to the 3's, etc. \r
\n" ); document.write( "\n" ); document.write( "When you finish with all the combos, up through 6+6. You will have a total of 21 combinations that could occur when rolling two fair dice.\r
\n" ); document.write( "\n" ); document.write( "If you look through them you will see that there are 3 combinations that will add up to 7.\r
\n" ); document.write( "\n" ); document.write( "So the probability that you will roll a sum of 7 is 3/21, which reduces to 1/7\r
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