Question 4 Adult movie tickets cost $4.00 more than tickets for children. Henry bought 3 tickets for adults and 9 tickets for children, and the total cost was $54.00. The situation can be represented by a system of equations.
Sy= x +4
9.2 + 3y = 54
What is the cost of one adult movie ticket?
A
$8.50
B.
$3.50
С
$11.50
D
$7.50

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?