Mr. sanchez’s class sold fruit pies for $1.32 each and mr. kelly’s class sold bottles of fruit juice for $1.77 each. together, the classes sold 90 items and earned $140.40 for their school.

(a) write and solve a system of equations that model the problem. show all your work.
(b) which class earned more money?
(c) how much more money did that class earn?

Including 6% sales tax, an inn charges $135.68 per night. find the inns nightly cost

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?

Divide. –4.2 ÷ 6 = a –0.7 b 0.7 c –7 d 7 me