Caitlyn spends $17 at the store. She buys a mop for $5 and 3 bottles of floor cleaner. If x represents the cost of each bottle of cleaner, the equation that can be used to find the value of x is 3 x + 5 = 17. Which shows the first step that should be taken to verify that $4 is the solution to the equation?
3 (4) minus 5 = 17
3 (4) = 17 + 4
3 (4) + 5 = 17 + 5
3 (4) + 5 = 17

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?