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edjones answered: 7568 problems
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I need the rate of work (R), the time of work (T) , and the work done (W)
the equation is RT = W.
It would help if I am provided a detailed explanation 1 solutions
Answer 181290 by edjones(7569) on 2009-12-11 19:04:53 (Show Source):
You can put this solution on YOUR website!Farmer does 1/4 the job in 1 hour.
Both do 1/3 the job in 1 hr.
Let the son do 1/x the job in 1 hr.
.
1/4 + 1/x = 1/3
3x+12=4x multiply each side by 12x (LCM) to eliminate fractions.
x=12 hrs it takes the son to do the job alone.
.
Ed
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logarithm/248760: I need the steps for entering 4+2log(5)/1-log(5) using a TI30xa.
The answer is 17.932, but I cannot come up with it using the calculator.
Thanks. 1 solutions
Answer 181242 by edjones(7569) on 2009-12-11 15:59:43 (Show Source):
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Probability-and-statistics/248757: I have a probability question....
10 percent of a yield is defective
the yield is 10
what is the probability that 5 will be defective? 1 solutions
Answer 181241 by edjones(7569) on 2009-12-11 15:41:20 (Show Source):
You can put this solution on YOUR website!Let x be defective and y be sound.
x=.1 y=.9
nCr = 10C5 = 252 coefficient of the squared binomial.
252x^5y^5 the 6th term of (x+y)^10
= 252*.1^5*.9^5
=.001488...
.
Ed
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Probability-and-statistics/248695: Amy and Martin play a game in which they take turns flipping a fair coin until one of them flips a head. The first person to flip a head is the winner. If Amy goes first, find the probability that she wins. 1 solutions
Answer 181240 by edjones(7569) on 2009-12-11 15:28:13 (Show Source):
You can put this solution on YOUR website!Chances of winning on that flip before the game begins.
A==M
1/2 1/4
1/8 1/16
1/32 1/64
.
1/8 / 1/2 = 1/4
1/32 / 1/8 = 1/4
This is an infinite geometric sequence.
r=1/4=.25
 Amy's probability of winning.
.
Ed
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Probability-and-statistics/248725: There are 5 pairs of socks in a drawer. 2 Blue pairs, 2 Black pairs and one gray pair. The socks are not folded together. If you randomly pick two socks, what is the probability that you will pick a matched pair? that you will pick a gray pair? 1 solutions
Answer 181236 by edjones(7569) on 2009-12-11 14:57:14 (Show Source):
You can put this solution on YOUR website!nCr=n!/((n-r)!r!)
There are 10 socks.
.
Pick a gray pair:
2C2 / 10C2 = 1/45
.
4C2 / 10C2 = 6/45 blue pair or black pair
.
Any pair: 6/45 + 6/45 + 1/45
=13/45
.
Ed
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Numeric_Fractions/248741: i have a multiple fractions equation & need to know how to calculate it (i am online with my ps3 so i cannot type it in a normal manner i'll use a / to represent the fraction) the problem is 2/3 - 5/9 + 5/6 = ? these three fractions together are confusing me terribly because i don't know where to start at 1 solutions
Answer 181234 by edjones(7569) on 2009-12-11 14:30:17 (Show Source):
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real-numbers/248746: The below line can represent what solution set. Select the best answer:
a. All integers less than 5
b. All real numbers greater than 0
c. All counting numbers less than 6
d. All irrational numbers between 1 and 5
______________________
1 2 3 4 5 1 solutions
Answer 181232 by edjones(7569) on 2009-12-11 14:21:27 (Show Source):
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Probability-and-statistics/248737: Suppose 39 newly created pairs of jeans are placed in a bin to be checked for quality. Of these, 4 will not be of high enough quality to sell. Suppose that two pairs of jeans are randomly selected, without replacement, from the bin. What is the chance that both pairs of jeans selected will be substandard? Please help me with this problem. Thanks! 1 solutions
Answer 181229 by edjones(7569) on 2009-12-11 14:13:35 (Show Source):
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Miscellaneous_Word_Problems/248705: Alice, Beth, and Carlie have ten identical red balloons. In how many ways can the girls split up the balloons such that each of them gets at least one red balloon? 1 solutions
Answer 181228 by edjones(7569) on 2009-12-11 14:01:03 (Show Source):
You can put this solution on YOUR website!This is the same as a 7 balloon problem where girl(s) can get none.
The answer is 36. I worked it out on paper but couldn't figure out a formula.
.
Ed
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Proportions/248718: The theoretical probability of undesirable side effects resulting from taking Pyrene is 1 in 15. If 180 people take Pyrene to relieve congestion, theoretically how many will encounter undesirable side effects? 1 solutions
Answer 181225 by edjones(7569) on 2009-12-11 13:19:37 (Show Source):
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Probability-and-statistics/248546: a bag has 2 red martbles 3 green marbles and 1 blue marble. if you randomly take out 2 marbles at once whats the probability of getting a blue and a green marble? 1 solutions
Answer 181145 by edjones(7569) on 2009-12-10 22:08:47 (Show Source):
You can put this solution on YOUR website!nCr=n!/((n-r)r!) Combination of n things taken r at a time.
.
2C6=15 all marbles
.
1C1=1 blue
3C1=3 green
2C0=1 red
.
(1*3*1)/15= 1/5 probability of getting a blue and a green.
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Ed
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Polygons/248418: How do you find the measure of an interior angle and an exterior angle given the number of sides of each regular polygon? and we have to round to the nearest Tenth if necessary.
14. 8
15. 9
16. 13 1 solutions
Answer 181034 by edjones(7569) on 2009-12-10 18:34:23 (Show Source):
You can put this solution on YOUR website!n=number of sides.
Int angle=(n-2)* 180/n degrees.
ext angle=360/n
.
14. n=8
6* 180/8 =135 deg int angle
360/8=45 deg ext angle.
.
Ed
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Equations/248372: A bottle filled with water weighs 9.6 kg. If the water by itself weighs 5 times as much as the bottle, What is the weight of the bottle? 1 solutions
Answer 181013 by edjones(7569) on 2009-12-10 17:41:40 (Show Source):
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Trigonometry-basics/248291: F(x)= x^3 - 6x2 +13x - 10
Find all the zeros of the function
thx! 1 solutions
Answer 180977 by edjones(7569) on 2009-12-10 16:39:34 (Show Source):
You can put this solution on YOUR website!x^3 - 6x2 +13x - 10=0
do the rational roots test by dividing +- a/d = +- 10/1
The possible rational factors are +- 10, 5, 2, 1
testing these we find that 2 is a zero.
next we divide x^3 - 6x2 +13x - 10 by x-2 and get x^2-4x+5 which is a quadratic.
x^2-4x+5=0
x^2-4x =-5
x^2-4x+4=-5+4 completing the square.
(x-2)^2=-1
x-2=+-sqrt(-1)
x=2+i, x=2-i the other 2 zeros.
.
Ed
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Numbers_Word_Problems/248101: Find a sequence of three intergers with a common difference of three, such that three times the sum of the first two intergers minus five times the largest interger is 61. 1 solutions
Answer 180865 by edjones(7569) on 2009-12-10 01:19:02 (Show Source):
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