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Recent problems solved by 'scott8148'
scott8148 answered: 6619 problems
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Not sure how to set this up.
1 solutions
Answer 365551 by scott8148(6628)   on 2012-01-30 16:14:27 (Show Source):
You can put this solution on YOUR website!"Chelsea eats 1/8 of the pizza, and Jeff eats 1/2 of the pizza" ___ 1/2 is 4/8
___ so C and J ate 5/8 of the pizza
___ that means T ate 3 eighths
so 3/8 of the pizza cost $6.63(nicely divisible by 3)
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Polynomials-and-rational-expressions/564189: I have a question that I am having trouble with can someone help me?
Find the LCM of z^2+10z+25 and z^2+z-20.
So what I came up with was I did the first equation and I got (z+5)^2 and I did the second equation and I got (z-4)(z+5). am I on the right track?
Thank you for your help
1 solutions
Answer 365298 by scott8148(6628) on 2012-01-29 11:22:19 (Show Source):
You can put this solution on YOUR website!you're doing fine
the LCM is the product of the factors ___ each factor is multiplied the maximum number of times that it occurs in any one of the components
in your case ___ (z + 5)^2 * (z - 4)
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Polynomials-and-rational-expressions/564187: I have attempted most of this myself however; I feel like I might have gotten a bit confused when it came to solving for 10,100,1000. This is due today! Thank you for your help!!!
An electric company charges $7.50 per month plus $0.09 for each kilowatt hour (kwh) of electricity used.
Use C as the total cost and n as the number of kwh. Write an expression that gives the total cost of n kwh of electricity.
C=7.50+0.09n
You can find the average cost per kwh by dividing total cost by number of kwh. Write the expression that gives the average cost per kwh.
C(kwh)=C/n
Find the average cost per kwh for 10 kwh, 100 kwh, and 1,000 kwh.
10 kwh You would first start by finding the overall cost
C=7.50+0.09(10)
C=7.50+0.90
C=0.84 kwh
Next plug in 0.84 for C and 10 for n.
C(kwh)=0.84/10
C(kwh)=0.084
100 kwh
C=7.50+0.09(100)
C=7.50+9
C=16.50
C(kwh)=16.50/100
C(kwh)=0.165
1000 kwh
C=7.50+0.09(1000)
C=7.50+90
C=97.50
C(kwh)=97.50/1000
C(kwh)=0.0975
As the number of kwh increases, what happens to the average cost of the kwh? Would the average cost ever fall below $0.09? If so, identify a value that supports your answer. If not, explain how you know.
As the number of kwh increases the average cost of the kwh decreases.
How many kwh should be purchased for the average cost to be $0.12 per kwh?
1 solutions
Answer 365294 by scott8148(6628) on 2012-01-29 11:15:33 (Show Source):
You can put this solution on YOUR website!your calculations for the 100 and 1000 are fine; you need to repeat the same technique from those on the 10 calculation
increasing the number of kwh lowers the average cost because the fixed cost portion of the bill ($7.50) is spread out over more kwh
the electric company charges $.09/kwh, so the average cost can never go below that value
___ the average will get closer to $.09 as the number of kwh increases and the fixed costs are spread of more kwh
$.12 = ($7.50 + $.09x) / x ___ .12x = 7.5 + .09x ___ .03x = 7.5 ___ x = 250
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Mixture_Word_Problems/564234: How much of a 25% alloy and how much of a 50% alloy should be mixed to make 1000g of a 45% alloy
I have tried:
.25x+.5y=.45(1000)
x+y=1000
y=3000 and X=-2000
Answer doesn't make sense
1 solutions
Answer 365286 by scott8148(6628) on 2012-01-29 10:52:44 (Show Source):
You can put this solution on YOUR website!your equations are fine
multiplying 1st eqn by -4 ___ -x - 2y = -1800
adding 2nd eqn to eliminate x ___ -x - 2y + x + y = -1800 + 1000 ___ -y = - 800
solve for y; then substitute back to find x
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Equations/563716: I have a word problem that I can't figure out. I do not know how to even begin to set up the equation. Here is the problem:
A large chess tournament is played in four different rooms at a community center. The number of players in the second room is twice the number of players in the first room. The number of players in the third room is three times the number of players in the second room. The number of players in the fourth room is four times the number of players in the third room. The tournament’s organizer claims there are “almost 200” players, and he’s correct. Exactly how many players are in the tournament?
I know that room 1 is x and room 2 is 2x, but after that I don't know what else to do. Can anyone help? Thanks in advance
1 solutions
Answer 365223 by scott8148(6628) on 2012-01-28 20:32:50 (Show Source):
You can put this solution on YOUR website!"third room is three times the number of players in the second room" ___ 3 * 2x = 6x
"fourth room is four times the number of players in the third room" ___ 4 * 6x = 24x
1x + 2x + 6x + 24x = 33x ___ x is an integer (there are no fractions of a player)
"The tournament’s organizer claims there are “almost 200” players, and he’s correct"
___ 6 * 33 = 198
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Equations/563924: I am trying to understand how this:
http://www.webcruiser.org/math/sample.jpg
gets simplified to this:
http://www.webcruiser.org/math/sample_simplified.jpg
Sorry about the links -- copy and paste doesn't present the characters properly.
1 solutions
Answer 365153 by scott8148(6628) on 2012-01-28 12:07:10 (Show Source):
You can put this solution on YOUR website!the .3 is distributed on the right-hand side; and then the entire right-hand side is subtracted to leave zero
the term on the left-hand side is combined with a similar term from the right-hand side subtraction
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Quadratic_Equations/563930: I have a bit of a problem with this word problem:
A ball is hit by a bat when 3 ft off the ground. It is caught at the same height 300 feet from the batter. How far from the batter did it reach its maximum height?
I was thinking 150 feet from batter, but that seems too simple. Any help?
1 solutions
Answer 365152 by scott8148(6628) on 2012-01-28 12:00:22 (Show Source):
You can put this solution on YOUR website!simple...but true (neglecting wind resistance)
the trajectory of the ball is a parabola, the axis of symmetry passes through the maximum height
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Mixture_Word_Problems/563112: How many gallons of a 60% antifreeze solution must be mixed with 80 gallons of 25% antifreeze to get a mixture that is 50% antifreeze?
Can you explain to me how to do this?
1 solutions
Answer 364765 by scott8148(6628) on 2012-01-26 13:47:21 (Show Source):
You can put this solution on YOUR website!(60%)(x) + (25%)(80) = (50%)(x + 80)
the sum of the amounts of antifreeze in the two solutions to be mixed, equals the amount of antifreeze in the final mixture
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Linear_Equations_And_Systems_Word_Problems/563065: Norma and Lauretta went to a store to buy DVDs on sale for $5 each,tax included. Norma purchased two and a half times as many DVDs as Lauretta purchased.Together they purchased 14 DVDs .Which system of linear equations can be used to determine n,the number of DVDs Norma puchased,and 1,the number of dvs lauretta purchased?
1 solutions
Answer 364764 by scott8148(6628) on 2012-01-26 13:40:32 (Show Source):
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Probability-and-statistics/563087: if a box contains 4 red balls, 5 blue balls, and 6 green balls, suppose that they are selected one by one until a green ball is found. what is the probability that it is necessary to examine at least 6 balls?
what i've tried. obviously, there are 15 balls total, and by the combination formula, 15 nCr 6 (in TI-83 language, in English, 15 choosing 6) there are 5005 possible combinations when you choose 6 from a total of 15. I am just stumped on how to get the numerator to divide by 5005.
Any insight would be greatly appreciated. Thank you.
1 solutions
Answer 364763 by scott8148(6628) on 2012-01-26 13:31:45 (Show Source):
You can put this solution on YOUR website!another way to look at the question ___ what is the probability of drawing 5 consecutive non-green balls?
ways to draw 5 of 15 ___ 15C5
ways to draw 5 of 9 ___ 9C5
(9C5) / (15C5)
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Numbers_Word_Problems/562814: If a number by 7 and the product is increased by 42 the result is 87 greater than twice the opposite of the number. Find the number...
This is a riddle my sister and I have been trying to figure out for days now, do you think you could find the answer ? :/ Please and Thankyou !!
1 solutions
Answer 364705 by scott8148(6628) on 2012-01-25 21:43:35 (Show Source):
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Polygons/562746: What is the ratio of the measure of an interior angle to the measure of an exteror angle in a regular hexagon? A regular decagon? A regular n-gon?
I figured out that a hexagon is 3:2 and a decagon is 4:1 but I need help with the n-gon with n as any real positive number
1 solutions
Answer 364696 by scott8148(6628) on 2012-01-25 21:13:24 (Show Source):
You can put this solution on YOUR website!an exterior angle is ___ 360º / n
an interior angle is complementary to that ___ 180º - (360º / n)
[180º - (360º / n)] / (360º / n) ___ (n / 2) - 1
check your hexagon calculation...
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Travel_Word_Problems/562726: train A traveled 20 mi h faster than train B. train A takes 3 hoursto go between two cities, and train B takes 4 hours to travel the same distance. how fast does each train travel? please help me!!!! i've tried everything it says in the book!!!
1 solutions
Answer 364666 by scott8148(6628) on 2012-01-25 20:23:37 (Show Source):
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Radicals/561678: simplify the expression sqrt50 + 12 sqrt8= The answer is supposed to be 34 sqrt2 but I keep getting 29 sqrt 2?
1 solutions
Answer 364373 by scott8148(6628) on 2012-01-24 12:53:13 (Show Source):
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Length-and-distance/561513: Grace is 4 ft. tall and standing in the light of a 20 ft. tall lamppost. her shadow is 8 ft. long. If she moves 1 ft. closer to the lamppost, by how much will her shadow decrease?
1 solutions
Answer 364371 by scott8148(6628) on 2012-01-24 12:29:23 (Show Source):
You can put this solution on YOUR website!using similar triangles ___ 4 / 8 = 20 / (d + 8)
"cross" multiplying ___ 4d + 32 = 160 ___ d = 32 ___ this is the starting distance from the lamppost
4 / s = 20 / (31 + s) ___ 4s + 124 = 20s ___ 31 / 4 = s
her shadow decreases 1/4 ft or 3 in
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Money_Word_Problems/561473: john has two rectangular mirrors that are similar. the lenght of the smaller mirror is 4 inches and the width is 6 inches. the width of the bigger mirror is 2 feet.
What is the lenght of the bigger mirror
1 solutions
Answer 364368 by scott8148(6628) on 2012-01-24 11:35:12 (Show Source):
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Radicals/561329: sqrt(x-6)+3=sqrt(x)
does this have a real solution?
first i subtracted the 3 over, squared both sides and ended up with x=(25/4) but when i plug that in, it was not a true statement.
then i started over and squared both sides like the original problem shows and got the square root equal to a negative so that would be "no real solution".
thank you for looking at this!!
1 solutions
Answer 364247 by scott8148(6628) on 2012-01-23 17:09:45 (Show Source):
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Trigonometry-basics/560942: This question involves radian measure. I'm really confused on how to answer this problem correctly. The problem states: express -5(pie symbol)/6 radians in degrees. I'm trying to learn this correctly. Can someone please help?
Thanks
1 solutions
Answer 364095 by scott8148(6628) on 2012-01-22 20:27:55 (Show Source):
You can put this solution on YOUR website!is this a second post?
a radian is the size of a central angle of a circle that subtends a circumferential arc that is the length of the radius
in English ___ if you cut a piece of pie (not pi) and the outer arc of the crust is the same length as the radius of the pie
___ then the angle of the point of the piece is one radian
since the circumference of a circle is 2*pi*r; 360º (a whole circle) equals 2pi radians
in your case, -5pi/6 is a negative angle of ___ (-5pi / 6)(360º / 2pi) or -150º
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Trigonometry-basics/560953: This question involves radian measure. I'm really confused on how to answer this problem correctly. The problem states: express -5(pie symbol)/6 radians in degrees. I'm trying to learn this correctly. Can someone please help?
Thanks
1 solutions
Answer 364092 by scott8148(6628) on 2012-01-22 20:22:56 (Show Source):
You can put this solution on YOUR website!a radian is the size of a central angle of a circle that subtends a circumferential arc that is the length of the radius
in English ___ if you cut a piece of pie (not pi) and the outer arc of the crust is the same length as the radius of the pie
___ then the angle of the point of the piece is one radian
since the circumference of a circle is 2*pi*r; 360º (a whole circle) equals 2pi radians
in your case, -5pi/6 is a negative angle of ___ (-5pi / 6)(360º / 2pi) or -150º
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Equations/560926: The sum of the digits of a two-digit number is 8. If the number is multiplied by 4, the result is 104. Write and solve a system of equations. Find the number.
I thought the system is x+y=8 and 4z=104
Although then I thought that the couldn't be solved by graphing becuase there is no z-axis, no substitution because the variables aren't the same to plug back into, and not elimination because there is not two like variables to be the same but opposite and eliminate. I know the number is 26 but I dont know the equations.
1 solutions
Answer 364080 by scott8148(6628) on 2012-01-22 19:42:17 (Show Source):
You can put this solution on YOUR website!t = tens digit ; u = units digit
"The sum of the digits of a two-digit number is 8" ___ t + u = 8
"If the number is multiplied by 4, the result is 104" ___ 4(10t + u) = 104
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