SOLUTION: The second section of mathematics paper contains 7 questions and a candidate must answer only 4 questions. In how many ways can the 4 questions be chosen (without regard to order)?

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Question 1172208: The second section of mathematics paper contains 7 questions and a candidate must answer only 4 questions. In how many ways can the 4 questions be chosen (without regard to order)?
Answer by ikleyn(52778) About Me  (Show Source):
You can put this solution on YOUR website!
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It is the number of combinations of 7 items taken 4 at a time


    C%5B7%5D%5E4 = 7%21%2F%284%21%2A3%21%29 = %287%2A6%2A5%29%2F%281%2A2%2A3%29 = 7*5 = 35.    ANSWER

Solved.

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On Combinations,  see introductory lessons
    - Introduction to Combinations
    - PROOF of the formula on the number of Combinations
    - Problems on Combinations
    - OVERVIEW of lessons on Permutations and Combinations
in this site.

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.