1. Four wheel bearings are to be replaced on a company vehicle, and the mechanic has selected the four replacement parts from a large supply bin. Unknown to the mechanic, 10% of the bearings are defective and will fail within the first 100 miles after installation. What is the probability that the company vehicle will have a breakdown due to defective wheel bearings before it completes tomorrow's 200-mile delivery route?
2. It has been estimated that one in five Americans suffers from allergies. The president of Hargrove University plans to randomly select 10 students from the undergraduate population of 1400 to attend a dinner at his home. Assuming that Hargrove students are typical in terms of susceptibility to allergies and that the college president's home happens to contain just about every common allergen to which afflicted persons react, what is the probability that at least 8 of the students will be able to stay for the duration of the dinner event? Source: World Almanac and Book of Facts 2009, p. 187.