Is 3! + 4! = 7! ?
Solution and Explanation
3! = 1 x 2 x 3 = 6
4! = 1 x 2 x 3 x 4 = 24
∴ 3! + 4! = 6 + 24 = 30
7! = 1 x 2 x 3 x 4 x 5 x 6 x 7 = 5040
∴ 3! + 4! ≠ 7!
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Concepts Used:
Permutations and Combinations
Permutation:
Permutation is the method or the act of arranging members of a set into an order or a sequence.
- In the process of rearranging the numbers, subsets of sets are created to determine all possible arrangement sequences of a single data point.
- A permutation is used in many events of daily life. It is used for a list of data where the data order matters.
Combination:
Combination is the method of forming subsets by selecting data from a larger set in a way that the selection order does not matter.
- Combination refers to the combination of about n things taken k at a time without any repetition.
- The combination is used for a group of data where the order of data does not matter.