Answer: where n represents the total number of objects, and r represents the number of objects being selected at a time.
Step-by-step explanation:
Combination is a collection of the items where the order doesn't matter. It is a way to calculate the total outcomes of an event where order of the outcomes does not matter.
The formula for the number of combinations of n things taken r at a time is
Formula:
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<span>Note: , where nPr is the formula for permutations of n objects taken r at a time.</span>
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Example:
<span>How many different committees of 4 students can be chosen from a group of 15?
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Answer:
<span>There are possible combinations of 4 students from a set of 15.</span>
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There are 1365 different committees.</span></span></span>