STAT1610 ASSIGNMENT 3 2024

Assessment 3: Attempt review 03/07/2024, 19:05




STA1610-24-Y ! Welcome Message ! Assessment 3

QUIZ




Started on Wednesday, 3 July 2024, 5:29 PM
State Finished
Completed on Wednesday, 3 July 2024, 6:46 PM
Time taken 1 hour 16 mins
Marks 20.00/20.00
Grade 100.00 out of 100.00


Question 1
Which one of the following statements is incorrect with regard to the normal
Complete
probability distribution?
Mark 2.00 out of
2.00




a. The standard normal distribution has a mean of 0 and standard deviation of
1.
b. The area to right of mean of a standard normal distribution is 0.5 and the
area left of the mean of a standard normal distribution is also 0.5 .



c. The 𝑧-score of the mean of a normal probability distribution is one.

d. 99.7% of the values of a normal random variable are within ±3 standard
deviation of the mean.

e. The smaller the value of the standard deviation, the narrow and steeper the
curve.




Question 2 Consider the standard normal distribution 𝑍 , which one of the following
Complete probabilities is incorrect?
Mark 2.00 out of
2.00
a. 𝑃 (−2.4 ≤ 𝑍 ≤ 0) = 0.0082
b. 𝑃 (0 ≤ 𝑍 ≤ 1.8) = 0.4641
c. 𝑃 (−2.4 ≤ 𝑍 ≤ 1.8) = 0.9559
d. 𝑃 (𝑍 ≥ −2.4) = 1 − 𝑃 (𝑍 ≥ 2.4)
e. 𝑃 (𝑍 ≤ −1.8) = 𝑃 (𝑍 ≥ 1.8)




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