Creating Content
Brilliant has three unfinished courses, at least one of which must be finished in a month. The staff have decided to hire some interns and let each of them choose a course he or she likes.
If each course needs at least three interns working on it, what is the least number of interns Brilliant needs to hire so that they can be sure of finishing at least one course in a month?
The answer is 7.
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1 solution
Worst case scenario (which is the case we are catering for), there is an even distribution of interns among the 3 courses.
The maximum number of interns that each course could have without meeting the needs of the course is 2.
2 × 3 = 6 interns.
Using the Pidgeonhole Principle , we can determine that 1 more intern will meet the needs of any of the courses.
Thus, 7 interns will guarantee at least 1 course can be finished.