document.write( "Question 428500: You roll a pair of dice five times. Find the following probability of you getting at LEAST one sum of 7.\r
\n" ); document.write( "\n" ); document.write( "I have trouble with the 'at least' and 'at most' probability problems. \r
\n" ); document.write( "\n" ); document.write( "is it, 5C1(6/36)^1 (1-30/36)^4 ?
\n" ); document.write( "I'm also unsure when to subtract the probability from one or when to not. \r
\n" ); document.write( "\n" ); document.write( "I also have to find the probability of getting at most one sum of 7. \n" ); document.write( "
Algebra.Com's Answer #297819 by sudhanshu_kmr(1152)\"\" \"About 
You can put this solution on YOUR website!
here at least means : in five times, at least one time the sum should be 7, it may be more than one times even all the five times.\r
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\n" ); document.write( "\n" ); document.write( "probability of getting sum of 7 in a pair of dice = 6/36 = 1/6\r
\n" ); document.write( "\n" ); document.write( "probability of not getting sum of 7 = 5/6\r
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\n" ); document.write( "\n" ); document.write( "probability of getting sum of 7 not a single time P(A) = 5C5(5/6)^5(1/6)^0 \r
\n" ); document.write( "\n" ); document.write( "= 3125/7776\r
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\n" ); document.write( "\n" ); document.write( "probability of getting sum of 7 at least one time P'(A)= 1 - P(A)\r
\n" ); document.write( "\n" ); document.write( "= 1 - 3125/7776\r
\n" ); document.write( "\n" ); document.write( "= 4651/7776\r
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\n" ); document.write( "\n" ); document.write( "you are welcome to clear any doubt..\r
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