Practice question · Numerical answer
A class has 18 students taking logic, 14 taking metaphysics, and 6 taking both. How many students take at least one of the two?
Hints
- Use inclusion-exclusion: add the two counts and subtract the overlap.
- Compute 18 + 14 - 6.
Show the answer
26
Why
. Answering 32 is the standard error, and it double-counts the six students who appear in both lists.
Practise Set Theory: Membership and Operations
The app has 4 more questions on this lesson, and keeps your place in the course. Philosophy I is free to start.
More questions on Set Theory: Membership and Operations
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