StatisticsdrillConditional probability from a table
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
A subscription service tabulates new customers by plan and sign-up channel (see the table). Among customers who signed up through the Web channel, what is the probability that a customer chose the Basic plan? Counts: Basic plan: Web 21, App 28, Store 157; Premium plan: Web 118, App 93, Store 77. Round to 4 decimal places.
What this problem teaches
The formula: P(Basic plan | Web) = count(both) / count(Web).
A hint if you get stuck
Given the channel means you only look at that column. Divide the cell by the column total.
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