document.write( "Question 655171: 9. If Steven can mix 20 drinks in 5 minutes, Sue can mix 20 drinks in 10 minutes, and Jack can mix 20 drinks in 15 minutes, how much time will it take all 3 of them working together to mix the 20 drinks?\r
\n" ); document.write( "\n" ); document.write( "I have tried averaging drink times. How long it takes for each person to make a drink and a few other things. I have not done word problems for 25 years so I am sure there is an easy way to solve it but my brain can not think of it. Thanks in advance for your help, I greatly appreciate! \n" ); document.write( "
Algebra.Com's Answer #408966 by nerdybill(7384)\"\" \"About 
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9. If Steven can mix 20 drinks in 5 minutes, Sue can mix 20 drinks in 10 minutes, and Jack can mix 20 drinks in 15 minutes, how much time will it take all 3 of them working together to mix the 20 drinks?
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\n" ); document.write( "This is considered a \"rate\" problem.
\n" ); document.write( "Steven's \"rate\" is 20 drinks per 5 mins = 20/5 = 4 drinks per minute
\n" ); document.write( "Sue's rate is 20 drinks per 10 mins = 20/10 = 2 drinks per minute
\n" ); document.write( "Jack's rate is 20 drinks per 15 mins = 20/15 = 4/3 = 4 drinks per 3 minutes
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\n" ); document.write( "Let x= time for all three to make 20 drinks
\n" ); document.write( "then
\n" ); document.write( "x(4/1 + 2/1 + 4/3) = 20
\n" ); document.write( "multiplying both sides by 3:
\n" ); document.write( "x(12 + 6 + 4) = 60
\n" ); document.write( "x(22) = 60
\n" ); document.write( "x = 60/22
\n" ); document.write( "x = 2.73 minutes
\n" ); document.write( "or
\n" ); document.write( "x = 2 minutes and 44 seconds
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