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39. Coffee Talk A study on the enhancing effect of coffee on long-term memory found that 35 participants given 200 mg of caffeine performed better on a memory test 24 hours later compared to the placebo group that received no caffeine.
a. There was a probability of 0.049 that the difference between the coffee group and the placebo group was due to chance. What do you conclude?
b. A group given a higher dose of 300 mg performed better than the 200 mg group, with a probability of 0.75 that this difference is due to chance. What do you conclude?
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Chapter 4 Solutions
MyLab Statistics with Pearson eText -- Standalone Access Card -- for Essentials of Statistics
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