Eric purchased three music CDs and a sweatshirt from a band's online store and received a 20% discount. He paid $56 for his purchase. The following week, the same store offered a 40% discount on all its products. Eric's friend Neil took advantage of the sale and bought one music CD and two sweatshirts for $48. Assuming that the actual prices of the music CDs and the sweatshirts are unchanged, how much was the band charging for each CD and sweatshirt? * A. $9 each CD, $37 each sweatshirt B. $10 each CD, $36 each sweatshirt C. $11 each CD, $35 each sweatshirt D. $12 each CD, $34 each sweatshirt

Two number cubes are rolled- one blue and one yellow. part a) find the probability that the blue cube is less than 3 and the product is 8. part b) is this event independent or dependent? explain why. your

3-12. write each answer with a reasonable number of figures. find the absolute uncertainty and percent relative uncertainty for each answer. (a) [12.41 (±0.09) + 4.16 (±0.01)] x 7.068 2 (±0.000 4) =? (b) [3.26 (±0.10) x 8.47 (±0.05)] - 0.18 (±0.06) =? (c) 6.843 (±0.008) x 104 + [2.09 (±0.04)- 1.63 (±0.01)] =?

Aprisoner is trapped in a cell containing three doors. the first door leads to a tunnel that returns him to his cell after two days of travel. the second leads to a tunnel that returns him to his cell after three days of travel. the third door leads immediately to freedom. (a) assuming that the prisoner will always select doors 1, 2 and 3 with probabili- ties 0.5,0.3,0.2 (respectively), what is the expected number of days until he reaches freedom? (b) assuming that the prisoner is always equally likely to choose among those doors that he has not used, what is the expected number of days until he reaches freedom? (in this version, if the prisoner initially tries door 1, for example, then when he returns to the cell, he will now select only from doors 2 and 3.) (c) for parts (a) and (b), find the variance of the number of days until the prisoner reaches freedom. hint for part (b): define ni to be the number of additional days the prisoner spends after initially choosing door i and returning to his cell.