document.write( "Question 307255: I'm not sure if this goes under \"Combinatorics\", as I've never heard of that term before, but here goes..\r
\n" ); document.write( "\n" ); document.write( "Jim can fill a pool carrying buckets of water in 30 minutes. Sue can do the same job in 45 minutes. Tony can do the same job in 1 1/2 hours. How quickly can all three fill the pool together? \n" ); document.write( "
Algebra.Com's Answer #219864 by nerdybill(7384)\"\" \"About 
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Jim can fill a pool carrying buckets of water in 30 minutes. Sue can do the same job in 45 minutes. Tony can do the same job in 1 1/2 hours. How quickly can all three fill the pool together?
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\n" ); document.write( "First, convert all rates to hours:
\n" ); document.write( "Jim: 1 pool per 30 min = 1 pool per .5 hour = 1/.5
\n" ); document.write( "Sue: 1 pool per 45 min = 1 pool per .75 hour = 1/.75
\n" ); document.write( "Tony: 1 pool per 1.5 hour = 1/1.5
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\n" ); document.write( "Let t = time for all three to fill pool
\n" ); document.write( "then
\n" ); document.write( "t(1/.5 + 1/.75 + 1/1.5) = 1
\n" ); document.write( "Multiplying both sides by 1.5:
\n" ); document.write( "t(3 + 2 + 1) = 1.5
\n" ); document.write( "6t = 1.5
\n" ); document.write( "t = 1.5/6
\n" ); document.write( "t = 0.25 hours
\n" ); document.write( "OR
\n" ); document.write( "t = 15 minutes
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