The annual profits that company a and company b earn follow a bivariate normal distribution company a's annual profit has mean 2000 and standard deviation 1000. company b's annual profit has mean 3000 and standard deviation 500 the correlation coefficient between these annual profits is 0.80. calculate the probability that company b's annual profit is less than 3900, given that company a's annual profit is 2300. a) 0.8531 b) 0.9192 c) 0.9641 d) 0.9744 e) 0.9953

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?