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Expert: - 9/8/2011


Question
Hello. If it isn't too much trouble, would you mind checking to see if my answers are correct for these problems? Thank you!

1.A magazine article cited the numbers on household income in Berea, KY as given by the U.S. Census Bureau. Was a sample or the population used?

My answer - Since the study on household income in Berea, KY is given by the U.S. Census Bureau, population is to be used. The Census looks at the entire population.

2. The cardinal number of the set {yellow, blue, red, green, indigo, orange, violet} is _________.

My answer - The cardinal number of the set is 7

3. Find the supplementary angle of 79°.
1. 11°          
2. 79°          
3. 101° - My answer          
4. 158°

4. The theoretical probability of undesirable side effects resulting from taking Grebex is 1 in 20. If 100 people take Grebex to lower their blood pressure, how many will encounter undesirable side effects?

My answer - 100*(1/20) = 5 people will encounter undesirable side effects

5. If the odds of winning a raffle are  3:290, what is the probability of winning?
1. 3/290
2. 290/293
3. 3/293 - My answer
4. 3/287

6. One thousand raffle tickets are sold for $5.00 each. One grand prize of $1000 and two consolation prizes of $100 each will be awarded. Jeremy purchases one ticket. Find his expected value.

My answer: -5 + 1000*1/1000 + 100*2/1000 = -$3.80

7. A bag contains 8 pink marbles, 5 green marbles and 10 brown marbles. What is the chance of drawing a pink marble? If a pink marble is drawn then placed back into the bag, and a second marble is drawn, what is the probability of drawing a green marble? Give solutions exactly in reduced fraction form, separated by a comma.

My answer:
Total number of marbles = 8 + 5 + 10 = 23
Pink marbles = 8
Green marbles = 5

(a) Chance of drawing a pink marble = 8/23
(b) Chance of drawing a green marble = 5/23

8/23, 5/23

Now, there is one that I keep going back and forth with, because it is a multiple choice answer, and I can't decided between 2 possibilities. At first, I chose number 3, and then went back, and thought, "Maybe it is number 4." Is it number 3?

Given the situation described, identify the type of sampling involved. A business owner asks all the chatty customers their opinion of the parking facilitates.
1. random sampling
2. systematic sampling
3. convenience sampling
4. stratified sampling
5. cluster sampling

Answer
The questions that have been answered all look right.
For the last question, it would be 3.

To be stratified, the questioneer would divide the people into different types, get an estimate of how many were in each type, and then base the percentage asked in each category on the number in each type.

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Scott A Wilson

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I can answer any question in general math, arithetic, discret math, algebra, box problems, geometry, filling a tank with water, trigonometry, pre-calculus, linear algebra, complex mathematics, probability, statistics, and most of anything else that relates to math. I can even tell you it takes me over 2,000 steps to go a mile, but is that relevant?

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Experience in the area; I have tutored people in the above areas of mathematics for almost two years in AllExperts.com. I have tutored people here and there in mathematics since before I received a BS degree almost 25 years ago. In just two more years, I received an MS degree as well, but more on that later. I tutored at OSU in the math center for all six years I was there. Most students offering assistance were juniors, seniors, or graduate students. I was allowed to tutor as a freshman. I tutored at Mathnasium for well over a year. I worked at The Boeing Company for over 5 years. I received an MS degreee in Mathematics from Oregon State Univeristy. The classes I took were over 100 hours of upper division credits in mathematical courses such as calculus, statistics, probabilty, linear algrebra, powers, linear regression, matrices, and more. I graduated with honors in both my BS and MS degrees. Past/Present Clients: College Students at Oregon State University, various math people since college, over 7,500 people on the PC from the US and rest the world.

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My master's paper was published in the OSU journal. The subject of it was Numerical Analysis used in shock waves and rarefaction fans. It dealt with discontinuities that arose over time. They were solved using the Leap Frog method. That method was used and improvements of it were shown. The improvements were by Enquist-Osher, Godunov, and Lax-Wendroff.

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Master of Science at OSU with high honors in mathematics. Bachelor of Science at OSU with high honors in mathematical sciences. This degree involved mathematics, statistics, and computer science. I also took sophmore level physics and chemistry while I was attending college. On the side I took raquetball, but that's still not relevant.

Awards and Honors
I earned high honors in both my BS degree and MS degree from Oregon State. I was in near the top in most of my classes. In several classes in mathematics, I was first. In a class of over 100 students, I was always one of the first ones to complete the test. I graduated with well over 50 credits in upper division mathematics.

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My clients have been students at OSU, people nearby, friends with math questions, and several people every day on the PC, and you're probably make one more.

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