week 5

1. Non text book problems to complete.

A. The emergency room at DC General Hospital is busy. Patients randomly arrive at a rate of 7 per hour. What is the probability that during any 90-minute period, the number of patients arriving is exactly 8? Or at least 10?

B. Multiple Choice

i. A shipment of 240 iPhones was received by the Apple Store. Generally, the defective rate on orders such as this is 15. If 7 iPhones are chosen at random without replacement, what is the probability that four are defective?

a. 0.0003069   b. 0.0005069   c. 0.0006069   d. 0.0007069

ii. What is the probability that at most 5 are defective?

a. 0.900   b. 0.925   c. 0.950   d. 0.999

iii. What is the probability that at least 1 of the chosen iPhones is defective?

a. 0.367 b. 0.435 c. 0.545   d. 0.633

iv. What is the variance in the number of defective iPhones?

a. 0.299586   b. 0.39986   c. 0.49986  d. 0.69986

 

2. Chapter Problems from the text book.

Chapter Five Work: p. 179: 5.3; p. 187: 5.9a; p. 187: 5.10b; p. 187: 5.16a; p. 187: 5.17a; p. 191: 5.29; p 194: 5.41

5: Discrete Probability Distributions

Standard Deviation of A Discrete Variable