StatisticsdrillBinomial: exactly k
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
Historically 10% of sales calls end in a sale. Out of the next 8, independent of each other, what is the probability that exactly 3 end in a sale? Round to 4 decimal places.
What this problem teaches
The formula: P(X = k) = C(n, k) p^k (1 - p)^(n - k).
A hint if you get stuck
P(X = k) = C(n, k) p^k (1 - p)^(n - k).
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