links to harder perms and comms Qs (1 Viewer)

jkwii

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i want to practice some more of these but it doesnt seem to be easy to finder really hard ones? help or post your own hard ones?
 

kurt.physics

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Here is a hard one

16 college students are going to the beach in 4 identical vans. Each van can hold exactly four students. How many ways can we distribute the students in the vans? (Two distributions are different if there are two students who ride together in one distribution but not in the other. If the same groups of students are together, it does not matter which van they ride in .)

=} Good Luck
 

u-borat

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i think every single past hsc exam for the last 10 (at least) years have had a decentish to hard probability question.

check them out.

kurt, is that 16!/4! x 4! x 4! x 4! x 4!

16! ways of arranging the students, divided by 4( 4!) to disregard permutations of the same 4 people in a van, then divide it by another 4! because you have 4 vans and it doesnt matter which van the same 4 people are in?
 

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