StatisticsdrillChi-square: expected count of a cell
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 survey cross-tabulates preferred contact method by age group. Under 40: email 16, phone 21, chat 118. 40 and over: email 89, phone 70, chat 57. If age group and contact method were independent, what count would be expected in the cell for under 40 and email? Round to 2 decimal places.
What this problem teaches
The formula: E = row total × column total / grand total. The observed count in this cell is 16. The chi-square statistic adds (observed - expected)² / expected over all six cells.
A hint if you get stuck
Expected count = row total × column total / grand total.
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