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On a scale of (1-10), how evil is this test? There are no trick questions, and all the problems are similar to what I have assigned for hw.
Imagine you are a music/philosophy/lit major, and your only friends in the world are a standard-normal distribution table and a scientifc
calculator.
Math 210 - Section 3 (Summer Session 2)
Date: July 25, 2005
Midterm 2
1. The table below lists the 10 closest stars to Earth along with
their distance in light years.
(a) What is the mean distance of a star on this list from Earth?
(b) What is the standard deviation?
2. (a) What is the range? (referring to the table in problem 1)
(b) What can you say about the distribution of stars in our stellar neighborhood
from (a), and your answer to 1?
3. If Z is a random variable drawn from a standard-normal distribution, what is:
(a) P(-0.5≤Z≤2.4)?
(b) P(Z≥2.32)?
(c) P(Z≤-1.41)?
4. If X represents the distance of a star randomly selected from among the 30
closest stars to Earth, and the distances to these stars are normally distributed
with μ=9.828 light years, σ=2.4154 light years, then what is the probability
that X is between 8 and 11 light years from Earth?
[Source: Royal Observatory, Greenwich, UK]
5. What percentage of these stars are greater than 8 light years from Earth?
(again referring to problem 3)
6. Please describe, in your own words, the Central Limit Theorem and when to apply it.
Try not to write a novel. A short paragraph is all that I am looking for.
7. Fish are often contaminated with mercury, which can be toxic at fairly low levels.
A study in the early 1990s measured the level of mercury in hair samples of
residents of Kuwait. 68 females participated in the study. The mean level
of mercury contamination for the participants was 4.05 micrograms of mercury
per gram of hair, with a sample standard deviation of 4.43 micrograms per gram.
Find an 88% confidence interval for the mean mercury level in hair samples
from Kuwaiti females.
Imagine you are a music/philosophy/lit major, and your only friends in the world are a standard-normal distribution table and a scientifc
calculator.
Math 210 - Section 3 (Summer Session 2)
Date: July 25, 2005
Midterm 2
1. The table below lists the 10 closest stars to Earth along with
their distance in light years.
(a) What is the mean distance of a star on this list from Earth?
(b) What is the standard deviation?
| Star Name | Distance (light years) |
| Proxima Centauri | 4.24 |
| Alpha Centauri A | 4.34 |
| Alpha Centauri B | 4.34 |
| Barnard's Star | 5.97 |
| Wolf 359 | 7.80 |
| Lalande 21185 | 8.19 |
| UV Ceti A | 8.55 |
| UV Ceti B | 8.55 |
| Sirius A | 8.68 |
| Sirius B | 8.68 |
2. (a) What is the range? (referring to the table in problem 1)
(b) What can you say about the distribution of stars in our stellar neighborhood
from (a), and your answer to 1?
3. If Z is a random variable drawn from a standard-normal distribution, what is:
(a) P(-0.5≤Z≤2.4)?
(b) P(Z≥2.32)?
(c) P(Z≤-1.41)?
4. If X represents the distance of a star randomly selected from among the 30
closest stars to Earth, and the distances to these stars are normally distributed
with μ=9.828 light years, σ=2.4154 light years, then what is the probability
that X is between 8 and 11 light years from Earth?
[Source: Royal Observatory, Greenwich, UK]
5. What percentage of these stars are greater than 8 light years from Earth?
(again referring to problem 3)
6. Please describe, in your own words, the Central Limit Theorem and when to apply it.
Try not to write a novel. A short paragraph is all that I am looking for.
7. Fish are often contaminated with mercury, which can be toxic at fairly low levels.
A study in the early 1990s measured the level of mercury in hair samples of
residents of Kuwait. 68 females participated in the study. The mean level
of mercury contamination for the participants was 4.05 micrograms of mercury
per gram of hair, with a sample standard deviation of 4.43 micrograms per gram.
Find an 88% confidence interval for the mean mercury level in hair samples
from Kuwaiti females.
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no subject
Date: 2005-07-25 05:29 pm (UTC)From:I was putting the test out there to see if there were any questions phrased so oddly that no one but myself knows what the hell I am asking. The math professor I graded papers for last semester had a habit of doing that on tests. He would have 1-2 weird, illogical questions that made sense only to himself and no one else knew anything. And 1 question like that can screw an entire class up, because everyone spends time trying to answer that one weird mysterious question.
I wish my students were as enthusiastic as you =) Sadly, pretty much all of them approach my class the way you would a root canal.