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Circles/378973: the central angle theta of a circle with radius 9 inches intercepts an arc 20 inches, find theta 1 solutions
Answer 270555 by robertb(4012) on 2010-12-06 02:08:29 (Show Source):
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Probability-and-statistics/381418: One thousand raffle tickets are sold for $2.00 each. One grand prize of $500 and two consolation prizes of $100 each will be awarded. Jeremy purchases one ticket. Find his expected value. 1 solutions
Answer 270553 by robertb(4012) on 2010-12-06 01:28:12 (Show Source):
You can put this solution on YOUR website!If you're asking for his EXPECTED EARNINGS, then it is computed as follows:
His chance of winning the grand prize is 1/1000. His earning then would be 500 - 2 = $498.
His chance of winning $100 is 2/1000, and his earning then would be 100 - 2 = $98.
His chance of losing (or not winning any) is 997/1000. He stands to lose -$2 in that case.
His expected earnings is then  . Thus he stands to lose $1.30 on the average.
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test/381386: Natalie spend 90 minutes doing her math and english homework. The time he spends on her math homework is a function of the time she stands on her english homework 1 solutions
Answer 270547 by robertb(4012) on 2010-12-06 01:10:00 (Show Source):
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Probability-and-statistics/381234: An elevator has 4 passengers and 8 floors. Find the probability that no 2 passengers get off on the same floor considering that it is equally likely that a person will get off at any floor. 1 solutions
Answer 270536 by robertb(4012) on 2010-12-06 00:45:14 (Show Source):
You can put this solution on YOUR website!8 floors, 4 passengers. I will assume that the passengers begin at the first floor all going up, and any passenger gets off BEGINNING at the 2nd floor only (no one gets off at the 1st floor!) We have to find the number of all ordered listings of four numbers out of seven, e.g., 2<3<7<8, 3<6<7<8, 4<5<6<8, etc. That can be done in 7C4 ways. The total numbers of ways 4 passengers can get off at 7 floors (starting at the 2nd!) is  . Therefore the probability is  .
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Geometry_Word_Problems/381354: I need a break down of this problem please. Not really good at word problems.
The property restoration company PuroServ is considering switching to new dehumidifiers. Their market research, considering the cost of the new machines and their efficiency, tells them that the switch would give them an 80% chance of making a $20,000 profit, a 15% chance of breaking even, and a 5% chance of losing $5,000. How much money does PuroServ expect to make with their new purchase? 1 solutions
Answer 270523 by robertb(4012) on 2010-12-06 00:08:58 (Show Source):
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Rectangles/380864: A rectangle with a diagonal of 18, a right angle and another angle equaling 62 degrees. how do you find the area? 1 solutions
Answer 270335 by robertb(4012) on 2010-12-05 06:43:34 (Show Source):
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Money_Word_Problems/380921: Determine the theoretical probability of the event that an applicant had a Math SAT in the range 500 - 599 or was admitted. (Round your answer to the nearest .01).
Math SAT
200-399 400-499 500-599 600-699 700-800 Total
Admitted 9 210 1124 2882 5309 9534
Not Admitted 687 3512 8689 12230 5150 30268
Total Applicants 696 3722 9813 15112 10459 39802
P(E) = 1 1 solutions
Answer 270330 by robertb(4012) on 2010-12-05 06:29:22 (Show Source):
You can put this solution on YOUR website!Determine the theoretical probability of the event that an applicant had a Math SAT in the range 500 - 599 or was admitted. (Round your answer to the nearest .01).
Math SAT
200-399 400-499 500-599 600-699 700-800 Total
Admitted 9 210 1124 2882 5309 9534
Not Admitted 687 3512 8689 12230 5150 30268
Total Applicants 696 3722 9813 15112 10459 39802
P(E) = 1
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N(500 - 599 or admitted) = N(500 - 599) + N(admitted) - N(500 - 599 and admitted)
= 9813 + 9534 - 1124 = 18223. Thus P(500 - 599 or admitted) = 18223/39802 = 0.46.
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Miscellaneous_Word_Problems/380938: A jar contains four coins: a nickel(5 cent), a dime(10 cent), a quarter(25 cent), and a 50-cent piece. Three coins are randomly selected from the jar.
a. List the sample point in S.
b. What is the probability that the selection will contain the 50-cent piece?
c. What is the probability that the total amount drawn will equal 60 cents or more? 1 solutions
Answer 270328 by robertb(4012) on 2010-12-05 06:15:23 (Show Source):
You can put this solution on YOUR website!a. The sample space : {{n,d,q}, {n,d,f}, {n,q,f}, {d,q,f}}, there are four sample points. Note that for each sample point order doesn't matter.
b. 3/4. {{n,d,f}, {n,q,f}, {d,q,f}}
c. 3/4. {{n,d,f}, {n,q,f}, {d,q,f}}
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Circles/380941: in a circle of radius 6 inches the length of the arc of a sector is 6 pie inches. what is the area of the sector? 1 solutions
Answer 270320 by robertb(4012) on 2010-12-05 05:25:54 (Show Source):
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Circles/380942: find the central angle of a circle which intercepts an arc 80pie centimeter with the radius of the circle is 20 centimeter. tnx. 1 solutions
Answer 270317 by robertb(4012) on 2010-12-05 05:19:22 (Show Source):
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absolute-value/380895: What is the solution set of the absolute value sentence |6x+8|>-4? I picked No Solution, and got it wrong. I thought absolute value was always positive. Could someone explain what the correct answer is, please? Thank You. 1 solutions
Answer 270292 by robertb(4012) on 2010-12-04 23:18:34 (Show Source):
You can put this solution on YOUR website!Absolute values are always NON-NEGATIVE, not only positive. The very fact that the absolute value expression is non-negative means that FOR ANY x VALUE you plug in, the inequality is always TRUE, and so the solution set cannot be empty, on the contrary, is the set of all real numbers. Now you know, dear student!
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Miscellaneous_Word_Problems/380865: Determine whether a correlation coefficient of r = -0.405 is significant at 5% level for a sample size of 22. r is not sifnificant at 5% or r is significant at 5% 1 solutions
Answer 270291 by robertb(4012) on 2010-12-04 23:08:22 (Show Source):
You can put this solution on YOUR website!Use the t-distribution for small samples.
The test statistic is  . Then  .
Degree of freedom is 22- 2 = 20.
For 20 df and one-tailed test, critical value is -1.725. Since -1.725 > -1.98, r is significant at the 5% level.
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