Question

Daniel is building a “learning tower.” A learning tower is a small structure that allows small children to help in the kitchen. The design plans that Daniel is using requires 12 boards of high quality lumber. At the local home improvement store, about 88% of the lumber would be high quality, meaning it would be free of defects and usable in this project. To account for lumber that may be discarded, Daniel purchases 15 boards of lumber from this store. (Assume that Daniel is in a hurry and does not have time to closely inspect the boards while at the store.)

Answer 1

What is the probability that Daniel will have enough high quality lumber to complete his project?

There is an 88% chance that each board Daniel purchases is high quality. Since Daniel purchases 15 boards in total, he has a (0.88)^15 ≈ 0.47 probability of having enough high quality lumber to complete his project.