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Permutations/261634: A basketball team has 12 players. There are 5 different positions on
a basketball team. A starting lineup consists of 5 players, each assigned
to one of the 5 positions. How many different ways can a coach select a
starting lineup? 1 solutions
Answer 192774 by edjones(7569) on 2010-01-27 00:34:14 (Show Source):
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Probability-and-statistics/260716: If a game were "fair," the payoff on a bet would be the same as the odds for the event. In one game, the odds for winning are 1:13. If the game were "fair," what would the payoff be for a $5 bet? Of course, game in casinos are designed to make a profit for the casino investors. Supposing the casino makes the payoff at 1:11 odds, what profit does the casino make on your winning bet? 1 solutions
Answer 192074 by edjones(7569) on 2010-01-25 11:19:55 (Show Source):
You can put this solution on YOUR website!1-13 means that out of every 14 events the bettor loses 13 $1 bets and wins one payoff of $13.
If the payoff is 11 the bettor loses 13 $1 bets and wins 1 payoff of $11 for a net loss of $2.
2/14=1/7= 14 2/7% profit the casino makes.
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Ed
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Probability-and-statistics/260717: Suppose you are playing a game of chance. If you bet $5 on a certain event, you will collect $200 (including your $5 bet) if you win. find the odds used for determining the payoff? 1 solutions
Answer 192068 by edjones(7569) on 2010-01-25 11:06:18 (Show Source):
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Triangles/260312: i have an isosceles triangle. One angle has 3x and the other angle has (x+50).
How to find the third angle 1 solutions
Answer 191738 by edjones(7569) on 2010-01-24 12:54:10 (Show Source):
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Parallelograms/260283: The diagonals of a rhombus have lengths of 12 centimeters and 16 centimeters. What is the length of one side of the rhombus? 1 solutions
Answer 191735 by edjones(7569) on 2010-01-24 12:49:25 (Show Source):
You can put this solution on YOUR website!The diagonals of a rhombus form right angles when they intersect. A right triangle is formed who's hypotenuse is a side of the rhombus.
16^2+12^2
=256+144
=400
sqrt(400)=20 cm
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Ed
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Quadratic_Equations/260286: i don't really understand the nature of roots in a quadratic function. it says: for what values of k does kx^2-2x+3=0 have two different real roots? i'm not sure what to plug in or how to continue on from here... 1 solutions
Answer 191732 by edjones(7569) on 2010-01-24 12:44:28 (Show Source):
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Circles/260303: Okay. So how do you find the area of a semi-circle if you already have the perimeter? I am solving a problem where the perimeter is 20 and it wants me to find the area of the semi circle. plz help me out!
Thankss! 1 solutions
Answer 191730 by edjones(7569) on 2010-01-24 12:27:56 (Show Source):
You can put this solution on YOUR website!The perimeter of a semi-circle is pi*d/2 + d
The perimeter has 2 parts: the circular part which is 1/2 the circumference of a circle and a flat part which is the diameter of the circle.
pi*d/2 + d=20
pi*d+2d=40
d(pi+2)=40
d=40/(pi+2)
r=20/(pi+2)
.
A=(pi*r^2)/2
=pi*(20/(pi+2))^2/2
=pi*(400/(pi+2)^2)*1/2
=200pi/(pi+2)^2 or 23.77
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Ed
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Geometry_Word_Problems/260201: 16. The length of the hypotenuse of a right triangle exceeds the length of the base by 2 cm and exceeds, twice the length of the altitude by 1 cm. Find the length of each side of the triangle. 1 solutions
Answer 191691 by edjones(7569) on 2010-01-24 10:06:11 (Show Source):
You can put this solution on YOUR website!b+2=c
b=c-2
.
2a+1=c
2a=c-1
a=(c-1)/2
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a^2+b^2=c^2
((c-1)/2)^2+(c-2)^2=c^2
(c^2-2c+1)/4 + c^2-4c+4=c^2
c^2-2c+1+4(c^2-4c+4)=4c^2
c^2-2c+1+4c^2-16c+16=4c^2
c^2-18c+17=0
(c-17)(c-1)=0
c=17
b=15
a=8
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Ed
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Average/260205: The average(arithmetic mean) of nine numbers is 9. When a tenth number is added the average of the ten numbers is also 9. What is the tenth number ?
a) 9/10 b) 10/9 c) 9 d) 10 1 solutions
Answer 191679 by edjones(7569) on 2010-01-24 09:41:21 (Show Source):
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Probability-and-statistics/260162: In a small class of 10 students, 3 did not do their homework. The professor selects half of the class to present solutions to do homework problems on the board, and records how many of those selected did not do their homework.
A. give a probability distribution
b. sketch its histogram
c. find expected value 1 solutions
Answer 191640 by edjones(7569) on 2010-01-24 02:04:11 (Show Source):
You can put this solution on YOUR website!nCr=combination of n things taken r at a time
.
10C5=252 the denominator for all of these
probability distribution:
all 5 did their homework 7C5/252=21/252=.0833
4 did, 1 didn't. (7C4 * 3C1)/252=35*3/252=.4167
3did, 2 didn't. (7C3 * 3C2)/252=35*3/252=.4167
2 did, 3 didn't (7C2 * 3C3)/252=21/252=.0833
Make the histogram from the above figures.
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The expectation is that 1 or 2 of the selected 5 didn't do their homework
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Ed
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