If 5 persons take 5 hours to cook for 100 people, how many people can be fed if 15 persons cook for 10 hours?

Answer: C. 600

Time required to cook for 100 people = 5 hours.
Total cooking time of 1 person for 100 people = 5 X 5 = 25 hours.
If 15 people cook for 10 hours, 15 x 10 = 150 hours.
25 hours 100 peoples food is cooked
so 150 hours = food for 600 people can be cooked.

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