Brad makes d dollars per hour as a cook at a deli. The table shows the number of hours he worked each week in June. Hours Brad Worked in June
Hours week
21.5 1
23 2
15.5 3
19 4
Write an expression for the amount of money Brad earned in June. Combine like terms in the expression.

Amachine that produces a special type of transistor (a component of computers) has a 2% defective rate. the production is considered a random process where each transistor is independent of the others. (a) what is the probability that the 10th transistor produced is the first with a defect? (b) what is the probability that the machine produces no defective transistors in a batch of 100? (c) on average, how many transistors would you expect to be produced before the first with a defect? what is the standard deviation? (d) another machine that also produces transistors has a 5% defective rate where each transistor is produced independent of the others. on average how many transistors would you expect to be produced with this machine before the first with a defect? what is the standard deviation? (e) based on your answers to parts (c) and (d), how does increasing the probability of an event a↵ect the mean and standard deviation of the wait time until success?

Me i’m stuck on all these questions besides the two bottom ones

Three friends are comparing the prices of various packages of golf balls at a sporting goods store. hector finds a package of 6 golf balls that costs $4.50.