SOLUTION: An environmental agency will randomly select 4 houses from a block containing 25 houses for a random check. How many total selections are possible? How many permutations are possib

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Question 1164446: An environmental agency will randomly select 4 houses from a block containing 25 houses for a random check. How many total selections are possible? How many permutations are possible?
Answer by ikleyn(52915) About Me  (Show Source):
You can put this solution on YOUR website!
.

If the order does not matter, then the problem is about combinations and the answer is


    C%5B25%5D%5E4 = %2825%2A24%2A23%2A22%29%2F%281%2A2%2A3%2A4%29 = 12650.



If, in opposite, the order does matter, then the problem is about permutations, and the answer is


    25*24*23*22 = 303600.

Solved, answered and explained.

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On Combinations and Permutations,  see the lessons
    - Introduction to Permutations
    - PROOF of the formula on the number of Permutations
    - Simple and simplest problems on permutations
    - Special type permutations problems
    - Problems on Permutations with restrictions
    - Introduction to Combinations
    - PROOF of the formula on the number of Combinations
    - Problems on Combinations
    - Miscellaneous problems on permutations, combinations and other combinatoric entities
    - Fundamental counting principle problems
    - Nice recreational problems on permutations

    - OVERVIEW of lessons on Permutations and Combinations
in this site.   //   I listed here the "introductory" lessons only . . .

Also,  you have this free of charge online textbook in ALGEBRA-II in this site
    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this online textbook under the topic  "Combinatorics: Combinations and permutations".


Save the link to this textbook together with its description

Free of charge online textbook in ALGEBRA-II
https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson

into your archive and use when it is needed.