Math Grouping Help: 20 Students, 4 Groups of 5, Different Schools

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SUMMARY

The problem involves dividing 20 students into 4 groups of 5 and determining the number of ways to assign these groups to 4 different schools. The correct mathematical formulation for grouping is given by the expression 20C5 * 15C5 * 10C5 * 5C5. For assigning groups to schools, the solution involves recognizing that there are 4 groups (balls) and 4 schools (slots), leading to 4! (factorial) ways to assign each group to a school. The confusion arises from misinterpreting the second part of the question, which should focus on the assignment of groups rather than individual students.

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Homework Statement



Divide 20 students in 4 groups of 5 each. Find the number of ways of doing this?
Also find how can these gropus be sent to 4 different schools?

The Attempt at a Solution



I get both the answers as:
20C5*15C5*10C5*5C5

But my book gives two different answers for the above 2 different question. Help Please!
 
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The first answer looks correct: you first pick 5 out of 20 for the first group, then 5 out of the remaining 15 for the second group, etc.

For the second question, I think you should forget about the students. You have 4 groups, and 4 schools to send them to. In abstract terms: you have 4 balls and 4 slots, how many possible ways are there to put each ball into one slot?
 

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