2020 AMC 10B Problems/Problem 5
Problem
How many distinguishable arrangements are there of 1 brown tile, 1 purple tile, 2 green tiles, and 3 yellow tiles in a row from left to right? (Tiles of the same color are indistinguishable.)
Solution
Let's first find how many possibilities there would be if they were all distinguishable, then divide out the ones we overcounted.
There are ways to order
objects. However, since there's
ways to switch the yellow tiles around without changing anything (since they're indistinguishable) and
ways to order the green tiles, we have to divide out these possibilities.
~quacker88
Solution 2 (2 second solve)
Assume that MAA is an immature bunch and guess , which happens to be the correct answer.
-fidgetboss_4000
Video Solution
~IceMatrix
See Also
2020 AMC 10B (Problems • Answer Key • Resources) | ||
Preceded by Problem 4 |
Followed by Problem 6 | |
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All AMC 10 Problems and Solutions |
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