SOLUTION: If a student has to answer exam with 15 questions, then there will be _____ ways that a student can answer the exam with 2 correct answers and 13 incorrect answers.

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Question 1175185: If a student has to answer exam with 15 questions, then there will be _____ ways that a student can answer the exam with 2 correct answers and 13 incorrect answers.
Answer by ikleyn(52779) About Me  (Show Source):
You can put this solution on YOUR website!
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C%5B15%5D%5E2 = %2815%2A14%29%2F2 = 15*7 = 105 ways.

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This problem is about COMBINATIONS.


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.