Question 260162
nCr=combination of n things taken r at a time
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10C5=252 the denominator for all of these
probability distribution:
all 5 did their homework 7C5/252=21/252=.0833
4 did, 1 didn't. (7C4 * 3C1)/252=35*3/252=.4167
3did, 2 didn't. (7C3 * 3C2)/252=35*3/252=.4167
2 did, 3 didn't (7C2 * 3C3)/252=21/252=.0833
Make the histogram from the above figures.
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The expectation is that 1 or 2 of the selected 5 didn't do their homework
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Ed