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put this solution on YOUR website!if seven can mix 20 drinks in 5 minutes,sue can mix 20 drinks in 10 minutes, jack can mix 20 drinks in 15 minutes,how much time will it take all 3 of them working togehter to mix 20 drinks?
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seven does 4 per minute
Sue does 2 per minute
jack does 4/3 per minute
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Together 22/3 drinks per minute
= 3/22 minutes per drink
3/22 x 20 = 30/11 minutes