StatisticsdrillCombinations: unordered choices
A statistics problem from Statisticsdrill. Solve it with one answer box, with a fresh sample on every attempt and the worked steps and spreadsheet function in the answer, and it is checked the moment you submit.
The task
An analyst must pick 3 of 8 survey questions to keep in a short form. The order of picking does not matter. How many different groups are possible? Give a whole number.
What this problem teaches
The formula: nCr = n! / (k! (n - k)!).
A hint if you get stuck
Order does not matter, so use nCr = n! / (k! (n - k)!).
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