[quote="Bunuel" ]At a food processing and packaging plant, identical packets of confectionary items are prepared at a constant rate by a packaging machine. Each packet contains 3 chocolates, 4 candied nuts and 2 chewing gums. The production rate of chocolates, candied nuts and chewing gums at the plant is 750, 975 and 575 units per hour respectively. All the produced items are immediately sent to a common quality checking machine that can process 3000 units of confectionary items per hour. 20 percent each of chocolates, candied nuts and chewing gums fail the quality check. The remaining items are sent to the packaging plant without any holdup or delay. Which of the following can represent the number of packets of confectionary items prepared by the packaging machine in one hour?
I. 195
II. 230
III. 280
A. I only
B. II only
C. III only
D. I and II only
E. I, II and III
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Each pack contains - 3 chocolates, 4 candied nuts and 2 chewing gums
No. of items made every hour - 750 chocolates, 975 candied nuts and 575 chewing gums
Total items made every hour = 750 + 975 + 575 = 2300
Since Quality Check Machine can check upto 3000 items in an hour, it can check our entire batch
No. of items that pass quality check = 80% of items sent in = 600 chocolates, 780 candied nuts and 460 chewing gums
Here comes the tricky part, we will first find out the limiting reagent, that is the max number of packs that can be built.
Let's say all chocolates are packed, therefore no. of packets = 600/3 = 200
For there to be 200 packets, there needs to be sufficient number of other items i.e 200* 4 = 800 candied nuts, however only 780 candied items are available. This rules out any number of packets more than 200.
Since there isn't an option where no option is correct, it is safe to say 195 packets is possible and correct answer is A