Rank of the word PUBLIC is?
Correct Answer: 582
Solution and Explanation
The rank of the word "PUBLIC" is:
= (4x5! + 4x4! + 0x3! + 2x2! + 1x1! + 0x0!) + 1
= ((4x120) + 96 + 0 + 4 + 1 + 0) + 1
= 480 + 100 + 2
= 582
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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.