Question 1201951
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If a 300 kg solution of 3% sugar concentration evaporates at the rate of 5 kg per hour, 
how many minutes will it take for the solution to become a 5% sugar-concentrated solution?
(A) 12
(B) 24
(C) 624
(D) 1240
(E) 1440
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<pre>
In this problem, concentration is the ratio of weight of the sugar to the weight of the mixture.


So, initial mixture contains  0.03*300 = 3*3 = 9 kg of sugar.


We want it would be  9/M = 5% = =.05 after evaporation, where M
is the final mass of the mixture  M = 9/0.05 = 900/5 = 180 kilograms.


So, 300-180 = 120 kilograms of water should evaporate.


At the rate of 5 kg per hour, it will take  120/5 = 24 hours = 24*60 = 1440 minutes.    <U>ANSWER</U>
</pre>

Solved and explained.


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