.
The number of all possible ways to select 5 different balls from the set of 5+3 = 8 balls is = = 56.
It is the number of all possible combinations of 8 balls taken 5 at a time.
(The order of balls does not matter, in this problem).
Of these 56 combinations, ONLY ONE contain 5 red balls.
Therefore, the probability the problems asks for is .
Solved, answered and explained.
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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.