Sam bought some apples by the pound. He sold half the apples for 50% more per pound than his purchase price. He then sold half of the remaining apples for 25% more per pound than his purchase price. He then sold the remaining 650 pounds of apples for 25% less per pound than his purchase price. If he had $2600 in total sales, what was Sam's purchase price, in cents per pound, for the apples?

Arandom sample of 15 observations is used to estimate the population mean. the sample mean and the standard deviation are calculated as 172 and 63, respectively. assume that the population is normally distributed. a. with 99 confidence, what is the margin of error for the estimation of the population mean? b. construct the 99% confidence interval for the population mean. c. construct the 95% confidence interval for the population mean. d. construct the 83% confidence interval for the population mean. hint: you need to use excel function =t. inv.2t to find the value of t for the interval calculation.