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scott8148 answered: 6619 problems
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1 solutions
Answer 270833 by scott8148(6628)   on 2010-12-06 19:26:29 (Show Source):
You can put this solution on YOUR website!"Mrs. Bruce lacks one year from being five times as old as her son"
so if you add one to her age , she will equal 5 times the son
___ B + 1 = 5s ___ B = 5s - 1
"Five years from now she will lack One year from being 3 time as old as her son will be then"
same technique , different numbers
___ (B + 5) + 1 = 3(s + 5) ___ B + 6 = 3s + 15 ___ B = 3s + 9
substituting the B equivalent from the 1st equation into the 2nd equation ___ (5s - 1) = 3s + 9
2s = 10 ___ s = 5
B = 3(5) + 9 ___ B = 24
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Surface-area/381140: The outside dimensions of a picture frame are 3 feet by 29 inches. If its inside dimensions are 1 2/3 feet by 22 inches, what is the area of the frame?
I've tried to do length times width on both sizes but the answer is a multiple choice and none of the answers I've come up with are a choice. Here's what I've tried...outside-- 36 inches x 29 inches= 1044 inches or 87 feet
inside-- 20 inches x 22 inches= 440 inches or 36.66 feet
answer choices are A) 137.33 ft2 B) 616 in2 C) 144.67 ft2 D) 604 in2
1 solutions
Answer 270387 by scott8148(6628) on 2010-12-05 17:02:41 (Show Source):
You can put this solution on YOUR website!you actually have found the answer , except for the final step
the inches of AREA that you have calculated are actually square inches (or in^2)
if you take the difference of your two calculations , you'll see the answer
FYI ... 144 in^2 = 1 ft^2
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Miscellaneous_Word_Problems/380171: There were 30 absences from Fahid's electronics class during the first week. Absenteeism dropped steadily to 6 absences during the ninth week. Estimate the number of absences during the fourth week.
I think the answer is 16, but I am unsure how to set up a function for this problem. thanks!
1 solutions
Answer 270000 by scott8148(6628) on 2010-12-03 20:06:56 (Show Source):
You can put this solution on YOUR website!over an 8 week period , the number of absences declined by 24
3 fewer absences per week
during the 4th week (3 weeks after the 1st week) you would expect 9 fewer absences than the 1st week
a = 33 - 3w ___ a is the number of absences , and w is the week
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Graphs/379390: What is the formula or method of coming up with a line that is perpendicular to and equation and passes through a specific point...
ex: equation of a line that is perpendicular to 3x-4y=10 and passes through (-1,2)
1 solutions
Answer 269375 by scott8148(6628) on 2010-12-01 21:49:43 (Show Source):
You can put this solution on YOUR website!perpendicular lines have slopes which are negative-reciprocals of each other
eg. 3/2 and -2/3
when the equation is in standard form (as in this problem) ; swapping the x and y coefficients
and changing one of the signs
will give the perpendicular line
to have the line go through a particular point , plug the coordinates into the equation
to get a new constant term
4x + 3y = 10 is perpendicular to 3x - 4y = 10
4(-1) + 3(2) = 2 ___ 4x + 3y = 2 goes through (-1,2)
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Rate-of-work-word-problems/378756: One pump can drain a pool in 7 minutes. When a second pump is also used together with the first, the pool only takes 2 minutes to drain. How long would it take the second pump to drain the pool if it were the only pump in use?
1 solutions
Answer 269021 by scott8148(6628) on 2010-12-01 00:29:25 (Show Source):
You can put this solution on YOUR website!in the 2 min it takes to drain the pool , the 1st pump drains 2/7 of the pool
the 2nd pump drains 5/7 of the pool in 2 min ___ it could drain the whole pool in [2 / (5/7)] min
14/5 min or 2 min 48 sec
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Travel_Word_Problems/378755: Jim can run 5 miles per hour on a level ground on a still day. One windy day, he runs 11 miles with the wind, and in the same amount of time runs 6 miles against the wind. what is the rate of the wind?
1 solutions
Answer 269014 by scott8148(6628) on 2010-12-01 00:24:15 (Show Source):
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Equations/378435: First i need to explain the drawings i have been given. I was given a triangle and a square. On each of the three sides of the triangle there is x-y, and on each side of the square there is just y. So adding (x-y)+(x-y)+(x-y) would give you the permiter of the triangle, and adding the 4 ys would give you the permiter of the square. Now the question is,the perimters of the square and the triangle are equal. Find (x,y) if three times the perimter of the square exceeds twice the perimter of the triangle by 24.
1 solutions
Answer 269012 by scott8148(6628) on 2010-12-01 00:17:54 (Show Source):
You can put this solution on YOUR website!"the perimters of the square and the triangle are equal" ___ 4y = 3(x-y)
"three times the perimter of the square exceeds twice the perimter of the triangle by 24" ___ 3(4y) = 2[3(x-y)] + 24
use substitution to find y ___ substitute 4y for 3(x-y) (in the 2nd equation)
then use the value of y to find the value of x (in the 1st equation)
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Graphs/378428: What is the vertex of the absolute value equation:(paranthesis means absolute value) y=(2x-3)+1. If I may ask as well how would it be graphed, not that you have to(I could just use that to check my own). Thanks in advance!
1 solutions
Answer 269008 by scott8148(6628) on 2010-12-01 00:04:13 (Show Source):
You can put this solution on YOUR website!y = abs(x) has a slope(s) of -1 & 1 with the vertex at the origin(0,0)
y = abs(2x) changes the slope(s) to -2 & 2
y = abs(2x-3) shifts the vertex 3/2 units to the right
y = [abs(2x-3)] + 1 shifts the vertex 1 unit up
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Miscellaneous_Word_Problems/378426: I need some help understanding a problem. I have changed the problem around some to make sure that I can do it myself. If you do steps, can you exaplin them to me please?
Use the formula s(t)= 16t to the power of 2,for the equation:
The CN Tower in Toronto, at 1915 ft, is the world’s tallest
self-supporting tower (no guy wires). How long would it
take an object to fall freely from the top?
1 solutions
Answer 269003 by scott8148(6628) on 2010-11-30 23:45:51 (Show Source):
You can put this solution on YOUR website!the formula is for an object starting from rest and undergoing a uniform acceleration (gravity)
s stands for the distance traveled in time t (s is in feet , t is in seconds)
you are given s (1915) and you need to find t
1915 = 16t^2
1915 / 16 = t^2
sqrt(1915 / 16) = t
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Money_Word_Problems/378684: the simple interest for a loan at 8% for 4 years requires $320. how much interest is requirerd for a loan of the same amount of money if it is made at 9%for 5 years
1 solutions
Answer 268999 by scott8148(6628) on 2010-11-30 23:33:03 (Show Source):
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Trigonometry-basics/378725: I need help with a word problem, please! I just can't seem to get the hang of how to do this problem, it seems to be too wordy.
A pole 80 feet tall is situated at the bottom of a hill that slopes up at an angle of 12.0 degrees. A guy wire from the top of the pole to the hillside forms an angle of 35 degrees with the top of the pole. Find the distance from the base of the pole to the guy wire's point of attachment.
Thank you so much!
1 solutions
Answer 268998 by scott8148(6628) on 2010-11-30 23:29:22 (Show Source):
You can put this solution on YOUR website!picture the bottom of the pole at the origin (0,0)
with the pole going up the y-axis , and the top at (0,80)
the equation of the hillside is ___ y = [sin(12º)]x
the equation of the guy wire is ___ y = [sin(-55º)]x + 80
solve for x at the intersection
substitute to find y at the intersection
use the distance formula (from the origin) to find the solution
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Linear_Equations_And_Systems_Word_Problems/378707: Please help me solve this one: I bought coloring books. The big coloring books have 100 pages for $8 while the small coloring books have 25 pages for $2. I paid $28 and got a total of 650 pages. How many of each did I buy?
1 solutions
Answer 268997 by scott8148(6628) on 2010-11-30 23:11:36 (Show Source):
You can put this solution on YOUR website!the price per page is the same for both sizes, so there is not enough information to determine the number of each
also , given the price per page , the total cost and total pages do not concur (shoplifting?)
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Mixture_Word_Problems/378605: A 15% acid solution is mixed with a 70% acid solution to produce 120 liters of a solution that is 40% acid. How much of each solution was used to create the mixture?
1 solutions
Answer 268911 by scott8148(6628) on 2010-11-30 20:54:10 (Show Source):
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Travel_Word_Problems/378589: Ok, so i have this problem. 2 planes are in different towns, they are 1220 km apart and plane one travels at 320 km/hr and plane two travels at 290 km/hr. they started at the same time, so how many hours until they meet? i used D= r x t. I found that t1 = 3.81 hrs and t2 = 4.21 hours. And I am stuck at this place. so did i not do something right with D= RxT? or what?
1 solutions
Answer 268909 by scott8148(6628) on 2010-11-30 20:47:39 (Show Source):
You can put this solution on YOUR website!the TIMES ARE EQUAL when the planes meet
you need to solve for D and then plug in to find the time
t = d / r ___ d1 + d2 = 1220
d1 / r1 = d2 / r2 ___ 290d1 = 320d2
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Evaluation_Word_Problems/378588: Suppose that one solution contains 50% alcohol and another solution contains 90% alcohol. How many liters of each solution should be mixed to make 9.5 liters of a 70% alcohol solution?
1 solutions
Answer 268907 by scott8148(6628) on 2010-11-30 20:40:07 (Show Source):
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Miscellaneous_Word_Problems/378582: Could you please show me how to work this problem so I know how to do it.
Perimeter of a rectangle. The perimeter of a rectangular backyard is 6x + 6 yards. If the width is x yards, find the binomial that represents the length.
I need to put it in the equation forms step by step so I can understand it. Hope someone can write it for me so I understand it...
Thank you
1 solutions
Answer 268904 by scott8148(6628) on 2010-11-30 20:36:20 (Show Source):
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Linear-equations/378563: i have to find the quadratic function  whose graph passes through the given points: (-1,6)(1,4)(2,9). I know the "x"s in the quadratic equation will correspond to the x-coordinates in the three ordered pairs, and I also know this will be a quadratic system. I took a stab at it, but I'm doubtful about it. What i have so far is:
which i THINK is 
Ok. that's as far as i got, and it's dubious at best!! Please help! how do i denote the quadratics using the given ordered pairs, then how do i arrive at just one quadratic equation?
1 solutions
Answer 268903 by scott8148(6628) on 2010-11-30 20:30:02 (Show Source):
You can put this solution on YOUR website!you're almost finished
you've generated a system of three equations in a, b, and c
just solve the system for the three values
6 = a - b + c
4 = a + b + c
9 = 4a + 2b + c
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Linear-equations/378510:
i have to find the quadratic function whose graph passes through the following given points: (-2,7)(1,-2)(2,3). I am REALLY not at all sure about this! I know my "x" in the quad eq. corresponds to the x-coordinate, and the "y" likewise, but how is this denoted, and how do you get just one quad eq. from a system of three? Please help! I'm not even sure where to begin! Thx!
1 solutions
Answer 268882 by scott8148(6628) on 2010-11-30 20:02:03 (Show Source):
You can put this solution on YOUR website!plugging the points into the general equation will give you a system of three equations in a, b, and c
just solve the system for the three values
7 = a(-2)^2 + b(-2) + c ___ 7 = 4a - 2b + c
-2 = a(1)^2 + b(1) + c ___ -2 = a + b + c
3 = a(3)^2 + b(3) + c ___ 3 = 9a + 3b + c
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Sequences-and-series/378345: Write a rule for the nth term of the arithmetic sequence that has the 2 given terms.
A(20)=240, A(15)=170
I understand how to write a rule for a sequence using the A(n)=A(1)+(n-1)d, but I do not understand how to get a rule without having the first term and common difference. Any help is really appreciated!
Thanks so much!
1 solutions
Answer 268836 by scott8148(6628) on 2010-11-30 16:50:06 (Show Source):
You can put this solution on YOUR website!you have the formula
how many differences between A(15) and A(20)?
what's the numerical difference between the terms?
5d = 240 - 170
plug the value of d into your formula to find A(1)
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Miscellaneous_Word_Problems/378285: Hello, could someone help me with this problem , I am not sure what steps it takes to solve, could you include the math steps to getting the answer ,for a study reference please.Thank you for your time.
.1) Jason had to submit five animation projects as per his syllabus in the final semesters. He scored 88, 72, 85, and 76 points out of 100 in four projects. What should be his score in the fifth project so that the average of all the projects is at least 83?
1 solutions
Answer 268811 by scott8148(6628) on 2010-11-30 15:40:13 (Show Source):
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Evaluation_Word_Problems/377731: Hello, this is a problem from my homework that my friend and i are having problems with please help us.
A deli sells ham sandwiches for 2$ and roast beef sandwiches for 3$. a group organizing a family reunion placed orders for 85 sandwiches. The bill came to be 218$ before tax. How many ham sandwiches were ordered?
1 solutions
Answer 268483 by scott8148(6628) on 2010-11-29 19:42:59 (Show Source):
You can put this solution on YOUR website!"orders for 85 sandwiches" ___ h + r = 85
"The bill came to be 218$" ___ 2h + 3r = 218
multiply the 1st equation by 2 , and subtract the result from the 2nd equation to ELIMINATE the h's
r = 218 - 170
substitute back to find h
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Geometry_proofs/377787: hi im having some trouble with helping my sister with her math homework.. her name is kelly and shes in geometry in middle school. She is currently studying medians altitudes, and perpendicular bisectors...
The problem that we need help on is
IF THE POINT LIES ON THE PERPENDICULAR BISECTOR OF A SEGMENT, THEN THE POINT IS EQUIDISTANT FROM THE ENDPOINTS OF THE SEGMENT
GIVEN: LINE l IS THE PERPENDICULAR BISECTOR OF SEGMENT BC; A IS ON l
PROVE THAT AB IS EQUAL TO AC
1 solutions
Answer 268466 by scott8148(6628) on 2010-11-29 19:18:17 (Show Source):
You can put this solution on YOUR website!here's the strategy
you can fill in all the little details for a "formal" proof
let M be the point of intersection of BC and the bisector
BM equals MC ___ definition of bisector (given)
angle BMA equals (congruent) angle CMA ___ right angles formed by the perpendicular are equal
(perpendicular is given)
AM equals AM (itself) ___ reflection identity
so triangle BMA equals (congruent) triangle CMA ___ SAS
AB equals (congruent) AC ___ Corresponding Parts of Congruent Triangles are Congruent
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Evaluation_Word_Problems/377762: How do i go about answering this?(and please explain):
To raise money for new football uniforms, your school sells silk screened T-shirts. Short sleeve T-shirts costs the school $5 each and are sold for $8 each. Long sleeve T-shirts costs the school $7 each and are sold for $12 each. The school spends a total of $2500 on T-shirts and sells all of them for $4200. How many of the short sleeve T-shirts are sold?
1 solutions
Answer 268455 by scott8148(6628) on 2010-11-29 18:46:49 (Show Source):
You can put this solution on YOUR website!buying the shirts ___ 5s + 7L = 2500
selling the shirts ___ 8s + 12L = 4200
the easiest technique is to ELIMINATE the L's
multiply the 1st equation by 12 and the 2nd equation by 7 , then subtract the results
60s + 84L = 30000
56s + 84L = 29400
subtracting ___ 4s = 600 ___ s = 150
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Linear_Equations_And_Systems_Word_Problems/377756: One number is 1 less than a second number. Twice the second number is 20 less than 4 times the first. Find the two numbers.
I have tried dividing 20 by 4 and adding 1 but that still does not work I know the answer is 11 and 12 but I would like to know how to figure it out on my own
1 solutions
Answer 268449 by scott8148(6628) on 2010-11-29 18:32:52 (Show Source):
You can put this solution on YOUR website!let f=first and s=second
"One number is 1 less than a second number" ___ f = s - 1
"Twice the second number is 20 less than 4 times the first" ___ 2s = 4f - 20
substituting the value of f ___ 2s = 4(s - 1) - 20
2s = 4s - 4 - 20 ___ 24 = 2s ___ 12 = s
f = (12) - 1 = 11
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Travel_Word_Problems/377752: Jack takes 7.5 hours to make a trip overseas in a prop plane. Later he discovers that he could have taken a jet and saved 2.5 hours of flying time. Find the speed of the jet if the jet travels 225 MPH faster than the prop plane. -Thank you soo much!
1 solutions
Answer 268443 by scott8148(6628) on 2010-11-29 18:25:03 (Show Source):
You can put this solution on YOUR website!d = r * t ___ the distance is the same for both planes
(j - 225) * 7.5 = j * (7.5 - 2.5)
7.5j - (7.5 * 225) = 5j
2.5j = 7.5 * 225 ___ j = 675
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Evaluation_Word_Problems/377700: I need help with this problem:
POPULATION DENSITY The population density D (in people/mi^2)in a large city is related to the distance x from the center of the city by D=5000x/(x^2+36). In what areas of the city does the population density exceed 400people/mi^2?
1 solutions
Answer 268439 by scott8148(6628) on 2010-11-29 18:18:21 (Show Source):
You can put this solution on YOUR website!substitute and solve for x ___ 400 < 5000x /(x^2+36)
400x^2 + 14400 < 5000x
2x^2 - 25x + 72 < 0
factoring ___ (2x - 9)(x - 8) < 0
if x < 4.5 , both factors are < 0 , so the product is >0
if x > 8 , both factors are >0 , so the product is >0
4.5 < x < 8
if you think about real life , businesses would be concentrated in the city center
with people living farther out , but becoming less populated into the suburbs
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