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edjones answered: 7568 problems
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1 solutions
Answer 265274 by edjones(7569)   on 2010-11-17 01:23:27 (Show Source):
You can put this solution on YOUR website!nCr=Combination of n things taken r at a time.
There is a total of 30 pens. Two have already been selected. 5 of 28 yet to be selected.
(3C0 * 25C5)/28C5
=53130/98280
=.5406 probability that no green pens will be obtained from a random drawing.
1-.5406=.4594 probability that at least 1 green pen will be obtained from a random drawing.
.
Ed
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Probability-and-statistics/372456: How do you solve:
In one town, 29% of all voters are Democrats. If two voters are randomly selected for a survey, find the probability that they are both Democrats.
Thank you very much!
1 solutions
Answer 265268 by edjones(7569) on 2010-11-17 00:57:30 (Show Source):
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Probability-and-statistics/372453: How do you solve:
Suppose you pay $2.00 to roll a fair die with the understanding that you will get back $4.00 for rolling a 2 or a 1, nothing otherwise. What is your expected net winnings?
Thank you very much!
1 solutions
Answer 265266 by edjones(7569) on 2010-11-17 00:54:41 (Show Source):
You can put this solution on YOUR website!You pay $12. to roll it 6 times. Each number comes up once. You win $8.
Your net winnings are 12-8=-$4
-4/6= -$2/3 or about -$0.67 expected net winnings per roll.
.
Ed
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Probability-and-statistics/372450: How do you solve:
An insurance company will insure a $220,00 home for its total value for an annual premium of $510. If the company spends $30 per year to service such a policy, the probability of total loss for such a home in a given year is 0.001 and you assume either total loss or no loss will occur, what is the company's expected annual gain (or profit) on each such policy?
Thank you!
1 solutions
Answer 265264 by edjones(7569) on 2010-11-17 00:43:53 (Show Source):
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Probability-and-statistics/372447: How do you solve:
Suppose one card is selected at random from an ordinary deck of 52 playing cards. Let A = event a queen is selected and B = event a diamond is selected. Determine P(B|A).
Thank you!
1 solutions
Answer 265263 by edjones(7569) on 2010-11-17 00:35:21 (Show Source):
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Probability-and-statistics/371943: How do you solve:
The manager of a pizza parlor (which operates 7 days a week) allows each of three employees to select one day off next week. Assuming the selection is done randomly and independently, find the probability that all three select the same day, given that all three select a day beginning with the same letter.
Thank you!
1 solutions
Answer 265016 by edjones(7569) on 2010-11-16 14:00:13 (Show Source):
You can put this solution on YOUR website!There are two sets of 2 days in the week that begin with the same letter. Let's say that they all chose a day beginning with S. For a single person the probability of choosing Saturday is 1/2.
It doesn't make any difference what the 1st one chooses. The others have to chose the same day as the 1st.
1/2 * 1/2 = 1/4 the probability that all three select the same day, given that all three select a day beginning with the same letter.
.
Ed
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Probability-and-statistics/371794: What is the probability that the number of heads will be less than or equal to 1200 out of 2500 tosses?
P{H<= 1200 when you toss a coin 2500 times}
define X_k ={5 if H; 10 if H <---- should be on next line in braket
Please show me how to solve this. I have been working on it for over a week and cant seem to figure it out.
1 solutions
Answer 264829 by edjones(7569) on 2010-11-16 01:23:36 (Show Source):
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Probability-and-statistics/371804: Which statement is true for the binomial distribution?
a. Probability of success remains constant from trial to trial
b. Three or more possible outcomes
c. Dependent trials
d. At least 10 observations
e. All are conditions of a binomial distribution
I know a and c are true. But not sure about the rest.
1 solutions
Answer 264826 by edjones(7569) on 2010-11-16 01:19:31 (Show Source):
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Probability-and-statistics/371326: The probability of a driver under the age of 20 being involved in an accident is 15%. An insurance company records the number of teenage drivers it takes until one is involved in an accident.
A) What is the probability that the company finds the first accident on the 4th driver?
B) What is the probability that it takes more than 5 teenage drivers to see the first accident.
C) What is the probability that it will take less than 4 drivers to see the first accident?
1 solutions
Answer 264757 by edjones(7569) on 2010-11-15 21:15:54 (Show Source):
You can put this solution on YOUR website!Geometric Probability Function = f(x)=p(1-p)^(x-1)
.
A).15(.85)^3=.0921
.
C)
1 driver .15
2 """""" .1275
3 """""" .1084
----------------add
=======>.3859
.
B)
.3859+.0921=.4780
1-.4780=.5220
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Ed
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Probability-and-statistics/371505: At the first tri-city meeting, there are 8 people from town A, 7 people
from town B, and 5 people from town C. If a council consisting of 5
people is randomly selected, find the probability that 3 are from town A
and 2 are from town B.
1 solutions
Answer 264740 by edjones(7569) on 2010-11-15 20:55:47 (Show Source):
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Probability-and-statistics/371641: How do you solve:
Greg Brueck has a .78 chance of making par on each hole of golf that he plays. Today he plans to play just three holes. Find the probability that he makes par on at least one of the three holes.
Thank you!
1 solutions
Answer 264732 by edjones(7569) on 2010-11-15 20:44:42 (Show Source):
You can put this solution on YOUR website!x=.78, y=.22
(x+y)^3
y^3=.0106 probability of NOT paring any hole.
1-.0106=.9894 the probability that he makes par on at least one of the three holes.
.
Ed
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Inverses/371643: Our Chapter is called Inverse Functions, this is the problem:
f(x) = x^3
Thanks for your time and help...
1 solutions
Answer 264726 by edjones(7569) on 2010-11-15 20:38:37 (Show Source):
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Geometry_Word_Problems/371663: The ratio of a quarterback's completed passes to attempted passes is 5 to 8. If he attempted find how many passes he completed. Round to the nearest whole number if necessary.
1 solutions
Answer 264718 by edjones(7569) on 2010-11-15 20:24:37 (Show Source):
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Probability-and-statistics/371645: How do you solve:
Two cards are drawn, without replacement, from a standard 52-card deck. Find the probability that:
a) both cards are the same color
b) the second card is a queen, given that the first card is an ace.
Thank you!
1 solutions
Answer 264717 by edjones(7569) on 2010-11-15 20:22:34 (Show Source):
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test/371631: The ratio of the side lengths of Square A to the side length of Square B is 12:10. The side length of Square A is 18 centimeters. What is the perimeter of Square B?
1 solutions
Answer 264698 by edjones(7569) on 2010-11-15 19:45:37 (Show Source):
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Probability-and-statistics/371615: How do you solve:
The manager of a pizza parlor (which operates seven days a week) allows each of three employees to select one day off next week. Assuming the selection is done randomly and independently, find the probability that all three select the same day, given that all three select a day beginning with the same letter.
Thank you!
1 solutions
Answer 264685 by edjones(7569) on 2010-11-15 19:30:38 (Show Source):
You can put this solution on YOUR website!There are two sets of 2 days in the week that begin with the same letter. Let's say that they all chose a day beginning with S. For a single person the probability of choosing Saturday is 1/2.
It doesn't make any difference what the 1st one chooses. The others have to chose the same day as the 1st.
1/2 * 1/2 = 1/4 the probability that all three select the same day, given that all three select a day beginning with the same letter.
.
Ed
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Probability-and-statistics/371593: How do you solve:
A single card is chosen at random from a standard 52-card deck. Find the odds against it being a king or a black face card.
Thank you!
1 solutions
Answer 264680 by edjones(7569) on 2010-11-15 19:17:40 (Show Source):
You can put this solution on YOUR website!There are 12 face cards; 1/2 of them are black; 4 of the 12 cards are kings, 2 red and 2 black.
P= 8/52 = 2/13 (6 black face cards and 2 red kings = 8)
Odds against= ratio of falures to successes = 44 to 8 = 11 to 2
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Ed
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