Hi peaky,Good question, and the short answer is
no, they're not the same thing. Let me separate the two, since our reply leaned on the "multiplication principle" and it's easy to blur it with case-counting.
Counting different cases means you split a problem into separate scenarios and
add them up - e.g., "Case 1: one child gets all
5 fruits, Case 2: fruits split
3-
2," and so on. That's an
OR / addition style of counting, and here it would be a nightmare (tons of cases).
The multiplication method is different. You break the task into a
sequence of independent decisions and
multiply the number of choices at each decision. It's an
AND style: decision
1 AND decision
2 AND decision
3...
That's exactly what's happening in this problem:
- Fruit
1 - give it to any of
4 children
- Fruit
2 - any of
4 children
- ... and so on for all
5 fruits
Each fruit is one independent decision with
4 options, so you multiply:
4 × 4 × 4 × 4 × 4 = 4^5. No case-splitting, no adding - just one clean chain of choices.
A smaller version to feel the difference: distribute
2 different fruits among
3 children.
- Fruit
1 -
3 choices, Fruit
2 -
3 choices -
3 × 3 = 9 ways.
Notice you never listed "cases" - you just multiplied the choices per fruit. If you
did try to count cases (both to same child, split between two children, etc.) and add them, you'd get the same
9, but the multiplication route is far faster.
So:
multiplication = a chain of independent choices multiplied together; case-counting = separate scenarios added together. For this question, the first one is the tool you want.
Answer: Apeaky
Hello, I also had the same confusion, thank you clarity. I want to know one more thing, By multiplication method you mean counting diffrent cases?