Answer :
A.) Yes, the conditions for inference are met.
To determine if the conditions for inference are met, we need to check the following:
- Randomness: The samples are randomly selected from coffee and espresso purchases, so the randomness condition is met.
- 10% Condition: This condition requires that the sample size should be less than 10% of the population. Assuming the coffee and espresso purchases are large enough, this condition is likely met.
- Large Counts Condition: We need to check if each sample has at least 10 successes and 10 failures:
- For coffee: 24 used their own cups (successes) and 50 - 24 = 26 did not (failures). Both are greater than 10.
- For espresso: 18 used their own cups (successes) and 50 - 18 = 32 did not (failures). Both are greater than 10.
Since all conditions are met (randomness, 10% condition, and large counts condition), we can proceed with constructing the confidence interval.