<PRE><B>Question 285456</B>
in the combined time (x), they each mix a FRACTION of the 20 total drinks


Steve mixes ___ x/5


Sue mixes ___ x/10


Jack mixes ___ x/15


the fractions sum to one (the whole)


(x / 5) + (x / 10) + (x / 15) = 1


6x + 3x + 2x = 30 ___ x = 30/11



this is a mathematical solution; since each person would most likely mix a whole number of drinks (not 2/3 of a drink),
the number is a good approximation to REALITY
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