Free Practice Question
PS · Problem Solving
555-605
Combinations
In a class of eighteen students, a decision is to be made regarding who will take on the roles of president and vice-president. Each student has the right to vote for any of their classmates. Given that all students are eligible for these positions, how many unique outcomes can arise from this election?
Answer Choices
Correct answer marked belowA
16
B
34
C
72
D
144
306
Correct
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Explanation
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Official Explanation
Official
To determine the number of ways to choose a president and a vice-president, we can break the process into two steps. Step 1: Choose a president. There are 18 students available, so there are 18 options for this choice. Step 2: Choose a vice-president. After…
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2
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S
SourodeepFeb 4, 2024
finally understood this
S
ShivangJul 24, 2024
Amazing
What this question tests
What it tests
Whether you can count arrangements and selections correctly — permutations vs. combinations.
Common trap
Overcounting: treating a selection as ordered when order does not matter, or forgetting to divide by duplicates.
Details
Difficulty
555-605
Type
PS
Category