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edjones answered: 7568 problems
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Probability-and-statistics/361724: Billy has 5 coins, 1 penny, 1 nickel, 1 dime, 1 quarter, and 1 half-dollar. How many different sums of money can Billy form by using 1, 2, or 3 of these coins?
1 solutions

Answer 257935 by edjones(7569) About Me  on 2010-10-26 01:53:07 (Show Source):
You can put this solution on YOUR website!
1) 5
.
2) 5C1*4C1=20
.
3) 5C1*4C2*3C1=60
.
Ed


Probability-and-statistics/361744: All of the following are characteristics that define a binomial random variable except
a. the outcome of one trial depends on the outcome of the previous trial.
b. outcomes are classified as either a success or a failure.
c. there are a fixed number of trials of an experiment.
d. the probability of a success is the same for each trial.

1 solutions

Answer 257932 by edjones(7569) About Me  on 2010-10-26 01:47:25 (Show Source):


Polynomials-and-rational-expressions/361750: (5)(-8)(2)
1 solutions

Answer 257931 by edjones(7569) About Me  on 2010-10-26 01:45:03 (Show Source):
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(5)(-8)(2)
=-80


absolute-value/361811: I need the process and the answer for this problem.
|2/5x+1/3|+2/3=4/5
1 solutions

Answer 257930 by edjones(7569) About Me  on 2010-10-26 01:41:57 (Show Source):


Probability-and-statistics/361820: Formulas: nCr = n! / r!(n-r)! Order not Imp.....

nPr = n! / (n-r)! Order is Imp....




Problem 1 (2 Points)

You are at a mountain resort and wish to dine at three different restaurants. A total of 8 restaurants are available, but only two of the eight serve sea food. However, you as a diner do not know that only two restaurants serve sea food. Find the number of ways in which you can select a restaurant for dining so that at least one of the selected restaurants will serve seafood. Assume that the order of selection is not important.
at least 1= 1 or more = 1 0r 2 or 3 or 4 or 5 or 6 or 7 or 8 = 8C1+8C2+ 8C3 +8C4+8C5+8C7+8C8= 255
1 solutions

Answer 257925 by edjones(7569) About Me  on 2010-10-26 01:27:21 (Show Source):
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2C2+(2C1)(6C1)
=1+2*6
=1+12
=13 the number of ways in which you can select a restaurant for dining so that at least one of the selected restaurants will serve seafood.
.
At least you are trying. You will get it. It's not brain surgery.
.
Ed


Probability-and-statistics/361823: A professor teaches a class of 60 students and another class of 40 students. Five percent of the students in each class are to receive a grade of “A”. In how many different ways can he distribute the “A” grades?
60 nCr 3= 34220
40 nCr 2= 780
34220+ 780= 35,000

1 solutions

Answer 257921 by edjones(7569) About Me  on 2010-10-26 01:15:45 (Show Source):
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.05*60=3
.05*40=2
.
60C3*40C2
=34,220*780
=26,691,600 ways
.
Ed


Probability-and-statistics/361825: A committee of four congressmen will be selected from a group of seven democrats and three republicans. Find the number of ways of getting exactly 4 democrats.
10 nCr 4 = 210
1 solutions

Answer 257915 by edjones(7569) About Me  on 2010-10-26 01:07:40 (Show Source):


Probability-and-statistics/361827: A set of three digits is provided {3, 4, 5}. How many five-digit numbers can be formed that begin and end with “3” if unlimited repetitions are allowed?
5 nPr 3= 60

1 solutions

Answer 257913 by edjones(7569) About Me  on 2010-10-26 01:00:35 (Show Source):
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1*3^3*1=27
.
Ed


Linear-systems/361831: Solve −9 + 24 ÷ ( −6) the steps on how It's done.
1 solutions

Answer 257912 by edjones(7569) About Me  on 2010-10-26 00:53:29 (Show Source):
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−9 + 24 ÷ ( −6)
=-9-4 do division & multiplication before adding or subtracting.
=-13
.
Ed


Graphs/361300: Determine whether the following lines are parallel, perpendicular, or the same line.
y = x + 1 and y = - x – 14
1 solutions

Answer 257691 by edjones(7569) About Me  on 2010-10-25 14:29:42 (Show Source):
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m[1]=1, m[2]=-1/1
Perpendicular.
graph%28500%2C500%2C-10%2C10%2C-10%2C10%2Cx%2B1%2C-x-14%29
.
Ed


Geometry_Word_Problems/361309: I am trying to find the length and width of a book. The book is 5cm longer than it is wide and the width is 84cm^2.
I was thinking about using the A=BH, but I'm not sure if it's the correct method.
1 solutions

Answer 257689 by edjones(7569) About Me  on 2010-10-25 14:14:35 (Show Source):
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Its width can't be in cm^2. It has to be in cm. Something is wrong.


Functions/361326: Given the function g(x)=x2+12x find the indicted values if g(3) and g(-5)
1 solutions

Answer 257688 by edjones(7569) About Me  on 2010-10-25 14:11:29 (Show Source):
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g(x)=x2+12x
g(-5)=(-5)^2+12*-5
=25-60
=-35
.
Ed


Radicals/361328: 1. ^3 sqrt of-64
2. sqrt of 27
3. sqrt of 2/7th
4. sqrt of 5 divided by sqrt of 12
1 solutions

Answer 257687 by edjones(7569) About Me  on 2010-10-25 14:08:16 (Show Source):
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2. sqrt(27)
=sqrt(9*3)
=3sqrt(3)
.
Ed


Polynomials-and-rational-expressions/361336: solve each equations.
8s2-16s=0
1 solutions

Answer 257686 by edjones(7569) About Me  on 2010-10-25 14:05:44 (Show Source):
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8s2-16s=0
8s(s-2)=0
s=0, s=2
.
Ed


Length-and-distance/361338: Suppose you have three straight sticks of lengths 5 cm, 12 cm, and 19 cm. Can you arrange these sticks into a triangle? If not, why not?
1 solutions

Answer 257684 by edjones(7569) About Me  on 2010-10-25 14:02:54 (Show Source):
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not so all the ends will touch.
5+12<19
.
Ed


Quadratic_Equations/361331: Hi, I was wondering if someone could possibly help me. I am supposed to do these homework questions in my Algebra class, but I am having a hard time getting started. I don't know what steps to go through to obtain the answer. The back of the book shows the answers, but that doesn't help me much. I need to show I got to the answer. If anyone could possibly assist me, by showing me how you obtained the answer, I would be forever grateful! :o)
(Section 11.1, Pg. 749, # 107)
Directions: In the following exercise use the compound interest formula
A=P(1+r) ^t to find the annual interest rate, r.
In 2 years, an investment of $1280 grows to $1445.
the answer in the back of the book is: 6.25%, but I have no idea how they got this answer. Your help is forever appreciated! :o)
1 solutions

Answer 257683 by edjones(7569) About Me  on 2010-10-25 13:59:36 (Show Source):
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A=P(1+r)^t
1445=1280(1+r)^2
(1+r)^2=289/256
1+r=1.0625 square root of each side.
r=.0625=6.25%
.
Ed


Pythagorean-theorem/361292: a painter leans a 20 foot ladder against a wall. The top of the ladder is 16 feet above the ground. How far is the bottom of the ladder from the wall?
1 solutions

Answer 257671 by edjones(7569) About Me  on 2010-10-25 13:38:28 (Show Source):
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a^2+b^2=c^2
a=16, c=20
256+b^2=400
b^2=144
b=12' dist of ladder from wall.
.
Ed


Divisibility_and_Prime_Numbers/361247: Find remainder when the sum 4^37 + 6^37 is divided by 25.
A) 5 B) 10 C) 15 D) 20 E) None

1 solutions

Answer 257653 by edjones(7569) About Me  on 2010-10-25 12:35:12 (Show Source):
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4^37 + 6^37 = 10^37
10^37= 1 followed by 37 zeros
There is no remainder when divided by 25. E
.
Ed


Polynomials-and-rational-expressions/361248: Find the polymonial function that has the given zeros.
2, 4+ square root 5, 4- square root of 5
I started out with this f(x)= (x-2)(x- 4+ or - square root of 5), but now I am stuck.
1 solutions

Answer 257652 by edjones(7569) About Me  on 2010-10-25 12:29:59 (Show Source):
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(x-2)(x-(4+sqrt(5))(x-(4-sqrt(5))
=(x-2)(x+sqrt(5)-4)(x-sqrt(5)-4)
=(x-2)(x^2-8x+11)
=x^3-10x^2+27x-22
.
Ed


Numeric_Fractions/361250: solve for n;12-11=25
1 solutions

Answer 257651 by edjones(7569) About Me  on 2010-10-25 12:20:52 (Show Source):
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There is no n in the problem.


Linear-equations/361271: find x
1/2(x-8)=1
show work

1 solutions

Answer 257649 by edjones(7569) About Me  on 2010-10-25 12:06:04 (Show Source):
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1/2(x-8)=1
x-8=2 multiply each side by 2
x=10
.
Ed


Rectangles/361173: can you help me with this problem. What is the maximum possible volume of rectangular box whose longest diagonal has fixed length L. thank you for helping me.



1 solutions

Answer 257648 by edjones(7569) About Me  on 2010-10-25 12:01:09 (Show Source):
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A square box has the largest volume.
x=length of each side of the square base of the box and the height of the box also, d=diagonal of base of box, L=diagonal of the box from bottom corner to opposite top corner.
d=xsqrt(2) hypotenuse of isosceles right triangle.
L^2=h^2+d^2
=x^2*(xsqrt(2))^2
=x^2*2x^2
=2x^4
L=x^2sqrt(2)
.
V=x^3 given
Ly=x^3 To find volume in terms of L we introduce a new variable, y, which, when multiplied by L equals the volume.
x^2sqrt(2)y=x^3 Substitute x^2sqrt(2) for L
y=x^3/x^2sqrt(2)
=x/sqrt(2)
=x/sqrt(2) * sqrt(2)/sqrt(2) Rationalizing the denominator.
=x*sqrt(2)/2
V=(L*x*sqrt(2))/2
.
Ed






Linear-equations/361178: find x
1350=0.25x+1750-.035x
show work

1 solutions

Answer 257639 by edjones(7569) About Me  on 2010-10-25 10:29:25 (Show Source):
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1350=0.25x+1750-.035x
1350=.215x+1750
-.215x=400
x=-1860.465116
.
Ed


Functions/361181: Please help!
Find the domain of the function.
g(x) = x/x^2-64
1 solutions

Answer 257638 by edjones(7569) About Me  on 2010-10-25 10:20:08 (Show Source):
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g(x) = x/x^2-64
x^2-64=(x+8)(x-8)
Since the denominator cannot equal zero x cannot equal 8 or -8
Domain: all real numbers except -8 and 8.
.
Ed
.
graph%28500%2C500%2C-10%2C10%2C-10%2C10%2Cx%2F%28x%5E2-64%29%29


Quadratic_Equations/361188: Please solve the quadratic equation by factors

2/x-2 + 3/x = 5/x-4


Please solve using the difference of two squares method

49a squared -4b squared
1 solutions

Answer 257637 by edjones(7569) About Me  on 2010-10-25 10:12:32 (Show Source):
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49a^2-4b^2
=(7a+2b)(7a-2b)
.
Ed


Probability-and-statistics/361108: How many ways can you deal the cards in a Klondike Solitaire game? (7 piles, the first pile having one card, the second having 2, the third having 3, etc. from a deck of 52 cards)
1 solutions

Answer 257603 by edjones(7569) About Me  on 2010-10-25 01:33:33 (Show Source):
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28 cards are dealt from a deck of 52 cards and the order dealt is important.
nPr=Permutations of n things taken r at a time.
52P28=426,384,982,032,100 ways.
.
Ed


Probability-and-statistics/361118: On a certain street are three traffic lights. At any
given time, the probability that a light is green is
0.3. What is the probability that a person will hit all
three lights when they are green if they represent
independent events?

1 solutions

Answer 257602 by edjones(7569) About Me  on 2010-10-25 01:25:21 (Show Source):


Probability-and-statistics/361076: A batch of 350 raffle tickets contains four winning tickets. You buy four tickets. What is the probability that you have
a.) no winning tickets?
b.) all of the winning tickets?
c.) at least one winning ticket?
d.) at least one non-winning ticket?
1 solutions

Answer 257601 by edjones(7569) About Me  on 2010-10-25 01:20:33 (Show Source):
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a) 346C4/350C4 = .9549
.
b)4C4/350C4=1/614597725
.
c) 1-.9549=.0451
.
d) 1- 1/614597725 = 614597724/614597725
.
Ed


Probability-and-statistics/361095: In testing a new drug, researchers found that 1% of all patients using it will have a mild side effect. A random sample of 15 patients using the drug is selected. Find th eprobability that:
A.) exactly one will have this mild side effect.
B.) at least one will have this mild side effect.
1 solutions

Answer 257599 by edjones(7569) About Me  on 2010-10-25 00:39:07 (Show Source):
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Let x=.99 and y=.01
(x+y)^15
A) 15x^14y=.1303 exactly one will have this mild side effect.
.
B x^15=.8601 none will have side affects.
1-.8601=.1399 at least one will have this mild side effect.
.
Ed


Proportions/361097: 3n(7n-20)=96
i have gotten to
21n squared -60=96
then im stuck :(
please expain how to work this or at least show the steps.
1 solutions

Answer 257597 by edjones(7569) About Me  on 2010-10-25 00:26:04 (Show Source):
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3n(7n-20)=96
21n^2-60n=96
21n^2-60n-96=0
21*-96=-2016
what two factors of -2016 have a sum of -60? -84 and 24.
21n^2+24x-84x-96=0
3n(7n+8)-12(7n+8)=0 Factoring by grouping.
(3n-12)(7n+8)=0
.
3n=12
n=4
.
7n=-8
n=-8/7
.
Ed


Probability-and-statistics/361101: A box contains three red balls, five black balls, and
four white balls. Suppose one ball is drawn at random.
Find the probability of each of the following
events:
a. A black ball is drawn.
b. A black or a white ball is drawn.
c. Neither a red nor a white ball is drawn.
d. A red ball is not drawn.
e. A black ball and a white ball are drawn.
f. A black or white or red ball is drawn.

1 solutions

Answer 257596 by edjones(7569) About Me  on 2010-10-25 00:06:43 (Show Source):
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12 balls total.
a) 5/12
b) 9/12=3/4
c) 5/12
d) 3/4
e) only one ball is drawn
f) 1
.
Ed