Worked scenario
Choose 4 Fruits From 9
This is a plain combination problem because order does not matter and each fruit can be used once.
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Worked counting problems with decision guidance
These pages bridge the gap between a raw formula and a real-world scenario, encouraging learners to decide on their own how to answer problems, with plenty of support in the details. This is where it gets interesting.
Worked scenario
Arrange 6 Books On a Shelf
This is a factorial or full permutation problem because all 6 distinct books are arranged in a row.
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Build a 3 Scoop Dessert From 5 Flavors
This is combination with repetition because the order of scoops does not matter, but the same flavor may appear more than once.
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Seat 7 Guests Around a Round Table
This is a circular permutation problem because rotating the full table does not create a new arrangement.
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Arrange the Word APPLE
This is a multiset permutation problem because the P appears twice, so duplicate swaps must be removed.
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Create 4 Digit Room Codes
This is permutation with repetition because the code positions are ordered and every position can reuse any symbol.
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