Explain two different methods for using combinations

AI Thread Summary
The discussion focuses on calculating the combinations of students that can travel on a bus with limited seating. The coach needs to select 45 students from 50, which can be calculated as 50 C 45, resulting in 2,118,760 combinations. Two methods for this selection are proposed: one involves directly choosing 45 students for the bus, while the other involves selecting the 5 students who will travel by car. Both methods yield the same total number of combinations, confirming their equivalence. The discussion seeks clarification on these methods and their outcomes.
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Homework Statement



A soccer coach organizing a field trip finds that 50 students have signed up. However, the bus has only 47 seats, so a few students will have to travel by car. The coach and one other coach must go on the bus. Explain two different methods for using combinations to find how each coach can choose which students go on the bus. Show that both methods produce the same answer.

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The Attempt at a Solution



I determined that the number of combinations of students on the bus is 50 C 45 = 2118760. However, I do not know how this can be done with two different methods. Could someone please help me? Thanks.
 
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I am not certain to what the question is referring, but it could be the following: for every 45 students that travel by bus there are 5 students that travel by car. We can either choose the 45 bus students (method 1) or we can choose the 5 car students (method 2).
 
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