Maria spent the day working at a DVD shop. They run a sale with $10 DVDs and $12 DVDs. Her boss wants to know the total number of $12 DVDs they sold. 500 customers bought DVDs but she doesn’t want to go through all the receipts. If she knows that they sold $5,750, how many did they sell?

Recall that the owner of a local health food store recently started a new ad campaign to attract more business and wants to know if average daily sales have increased. historically average daily sales were approximately $2,700. the upper bound of the 95% range of likely sample means for this one-sided test is approximately $2,843.44. if the owner took a random sample of forty-five days and found that daily average sales were now $2,984, what can she conclude at the 95% confidence level?