BUAL 2650 (CHEN YAN) FINAL EXAM UPDATED ACTUAL QUESTIONS AND CORRECT ANSWERS

BUAL 2650 (CHEN YAN) FINAL EXAM UPDATED ACTUAL
QUESTIONS AND CORRECT ANSWERS

Question:
1. What is quantitative value that represents the outcomes from an experiment?
Answer:
Random Variable

Question:
2. What are the 2 kinds of random variables?
Answer:
discrete (countable) and continuous (decimals)

Question:
3. What is the most common type of continuous probability distribution?
Answer:
normal distribution

Question:
4. What are some other names for a continuous probability distribution?
Answer:
probability curve and probability density function (pdf)

Question:
5. What is the total area under the curve if f(x) always equal to?
Answer:
1 or 100%

Question:
6. What is an area under a continuous probability distribution?
Answer:
a probability

Question:
7. How many types of normal curves are there?
Answer:
an infinite amount

Question:
8. What does the shape of any individual normal curve depend on?
Answer:
its specific mean and standard deviation (also median and mode)

Question:
9. What is the highest point over?

,Answer:
the mean, median, mode

Question:
10. Is the normal curve symmetric?
Answer:
yes (left and right are mirror images)

Question:
11. What does a larger standard deviation do to a curve?
Answer:
makes it shorter and wider

Question:
12. Do the tails of a normal curve ever touch the horizontal axis?
Answer:
no

Question:
13. What percent of the area under the normal curve is within 1 standard deviation to the left and right?
Answer:
68.26

Question:
14. What percent of the area under the normal curve is within 2 standard deviation to the left and right?
Answer:
95.44

Question:
15. What percent of the area under the normal curve is within 3 standard deviation to the left and right?
Answer:
99.73

Question:
16. How do you calculate a z-score?
Answer:
(value-mean)/standard deviation

Question:
17. What is the difference between x and z?
Answer:
x is normal distribution where z is standard normal distribution

Question:
18. What is cumulative probability?

, Answer:
means less than, the left side under curve

Question:
19. What must you do to find probability to the right of a Z score?
Answer:
1 - value from Z table

Question:
20. P (z< 2)
Answer:
0.9772

Question:
21. P (z<1.25)
Answer:
0.8944

Question:
22. P (z>2.3)
Answer:
0.0107

Question:
23. P (-1 < z< 2)
Answer:
0.8185

Question:
24. Suppose x is a normally distributed variable from N(300, 15). P(x>280)
Answer:
0.9082

Question:
25. Find Z0.025
Answer:
1.96

Question:
26. What is xbar?
Answer:
the sample mean

Question:
27. What is n?