Customers arrive at a single self-serve coffee machine in a busy mall at the rate of 20 per hour, following Poisson distribution. Each customer takes exactly 90 seconds to get his or her coffee. What is the expected number of customers in queue at this coffee machine

Thompson and thompson is a steel bolts manufacturing company. their current steel bolts have a mean diameter of 127 millimeters, and a variance of 36. if a random sample of 35 steel bolts is selected, what is the probability that the sample mean would differ from the population mean by greater than 0.5 millimeters? round your answer to four decimal places.

Rhombus adef is inscribed into a triangle abc so that they share angle a and the vertex e lies on the side bc . what is the length of the side of the rhombus if ab=c, and ac=b.

What adds to be the bottom number but also multiplies to be the top number with 8 on the bottom and 15 on top