6. The triangles at the right are similar. a. What are the lengths of sides DF and EF?

b. What is the scale factor from triangle DEF to triangle ABC?

c. What is the scale factor from triangle ABC to triangle DEF?

The square pyramid has a volume of 441 cubic inches. what is the value of x? 1/7x is the height x is the base

Paul’s car is 18 feet long. he is making a model of his car that is 1/6 the actual size. what is the length of the model?

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?