2018 AMC 10B Problems/Problem 3
Contents
[hide]Problem
In the expression each blank is to be filled in with one of the digits or with each digit being used once. How many different values can be obtained?
Solution 1 - Combinations
We have ways to choose the pairs, and we have ways for the values to be rearranged, hence
Solution 2
We have four available numbers . Because different permutations do not matter because they are all addition and multiplication, if we put on the first space, it is obvious there are possible outcomes .
Solution 3
There are exactly ways to arrange the numbers and overcounts per way due to commutativity. Therefore, the answer is
~MC_ADe
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See Also
2018 AMC 10B (Problems • Answer Key • Resources) | ||
Preceded by Problem 2 |
Followed by Problem 4 | |
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