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- Normal Distribution and Z-score
Normal distribution and continuous random variable
- Intro Lesson10:20
- Lesson: 1a4:52
- Lesson: 1b5:27
- Lesson: 1c3:34
- Lesson: 2a2:31
- Lesson: 2b3:11
- Lesson: 2c4:58
- Lesson: 3a3:23
- Lesson: 3b4:02
- Lesson: 3c6:08
Normal distribution and continuous random variable
Lessons
- Introduction
⋅ Why are z-scores needed for random continuous variables?
⋅ Relationship between area under the curve and probability
⋅ Leads to Standard normal distribution
- 1.Reading the Z Table
Use the Z table to find:a)the z-score when the area under the curve to the left of z is 0.3015.b)the area from the mean to a z-score of 1.45.c)the z-score when the area under the curve to the left of z is 0.7774. - 2.Finding Probabilities from Z-Scores
Answer the following questions based on the properties of standard normal distribution.a)What is the probability of having a z-score that is less than 0.75?b)What is the probability of having a z-score that is greater than -1.83?c)What is the probability of having a z-score that is between -1.27 to 1.06? - 3.Finding Z-Scores from Areas
Answer the following questions based on the properties of standard normal distribution.
i) by Z table
ii) by calculator
a)Find the z-score that represents the bottom 70%.b)Find the z-score that represent the top 70%.c)Find the z-scores that represent the top 4% and the bottom 4%.