Normal distribution & Probability
The grades of a group of 5000 students in an exam are normally distributed with a mean of 75 and a standard deviation of 5. A student from this group is selected randomly.
(i) Find the probability that his/her grade is greater than 90.
(ii) Find the probability that his/her grade is less than 50.
(iii) Find the probability that his/her grade is between 50 and 75.
(iv) Approximately, how many students have grades greater than 75.
34
Answer
Answers can only be viewed under the following conditions:
- The questioner was satisfied with and accepted the answer, or
- The answer was evaluated as being 100% correct by the judge.

4.8K
The answer is accepted.
Join Matchmaticians Affiliate Marketing
Program to earn up to a 50% commission on every question that your affiliated users ask or answer.
- answered
- 1050 views
- $20.00
Related Questions
- What Are The Odds ?
- Proper Test Selection for Repeated Interval Data Collection?
- standard deviation question (EASY)
- Draw a token from a bag of 9 blue tokens and 1 red token
- Describing Bayes Theorem succinctly in words
- Causality Question
- Explain how the mean of discrete variables is $\mu = \sum[x P(x)]$
- Statistics for argumentative data and politics