Mathematics

Mathematics

Problem

There are 29 students in the woodwind section of the school orchestra. 11 students can play the flute, 15 can play the clarinet, and 12 can play the saxophone. 4 can play the flute and the saxophone, 4 can play the flute and the clarinet, and 6 can play the clarinet and the saxophone. 3 students can play none of the three instruments. a. Display the information on a Venn diagram. b. Hence find the number of students in the woodwind section who can play: - all of the instruments mentioned - only the saxophone - the saxophone and the clarinet, but not the flute - exactly one of the clarinet, saxophone, or flute.
Intuitive explanation

This is a classic inclusion-exclusion principle problem where you need to account for overlaps carefully. The key insight is that when you add up all the individual instrument counts, you've overcounted students who play multiple instruments—so you subtract the pairwise overlaps, then add back the triple overlap (which got subtracted too many times). Start by figuring out how many students play at least one instrument, then use the given overlaps to find the missing piece: students who play all three.

Intuitive explanation

This is a classic inclusion-exclusion principle problem where you need to account for overlaps carefully. The key insight is that when you add up all the individual instrument counts, you've overcounted students who play multiple instruments—so you subtract the pairwise overlaps, then add back the triple overlap (which got subtracted too many times). Start by figuring out how many students play at least one instrument, then use the given overlaps to find the missing piece: students who play all three.

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