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Money_Word_Problems/468729: Luke spends 12% of his weekly salary on dining out. Of the money spent dining out, 55% or $39.60, is spent on fast food. What is Luke's weekly salary?
1 solutions

Answer 321593 by rfer(12657) About Me  on 2011-07-09 19:26:26 (Show Source):
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39.60/0.55=72
72/0.12=$600


Linear-equations/468663: Please help me with this algebra problem.
If Barbara recieved a 4 percent raise and is now making $41,200 per year. What was her salary before the raise? Round your answer to the nearest dollar.
1 solutions

Answer 321572 by rfer(12657) About Me  on 2011-07-09 16:40:23 (Show Source):
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41200/1.04=$39,615.00


Linear-equations/468670: Please help me with this algebra problem.
Given the linear equation y=-3/2x+1
Find the y coordinates of the points (-4), (-2) and (6) Please show work.
1 solutions

Answer 321570 by rfer(12657) About Me  on 2011-07-09 16:38:17 (Show Source):
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y=-3/2*-4+1
y=-6+1
y=-5


Equations/468653: i started with -3x+2x+1=4, and when -x-3=0 becomes x=-3 how does that happen?

1 solutions

Answer 321565 by rfer(12657) About Me  on 2011-07-09 15:25:07 (Show Source):
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-3x+2x+1=4
-x+1-1=4-1
-x=3
-1*-x=3*-1
x=-3


Linear-equations/468652: The line: y = 0.14x + 0.77 represents an estimate of the average cost of gasoline for each year. The line 0.11x - y = -0.85 estimates the price of gasoline in January of each year.
Use the equations of the lines to determine if they are parallel. What did you find?
Explain why you would expect the two lines to be intersecting, parallel, or perpendicular (chooseone)?
1 solutions

Answer 321564 by rfer(12657) About Me  on 2011-07-09 15:04:08 (Show Source):
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y=0.14x+0.77
y=0.11x+0.85
Different slope, no parallel or perpendicular
but will intersect


Linear-equations/468524: Please help me with this algebra problem. Thanks so much in advance.
Simplify and show all work please
12 divided by 1/4 + 2/5 - 2^3
1 solutions

Answer 321536 by rfer(12657) About Me  on 2011-07-09 12:08:29 (Show Source):
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12*4/1+2/5-8=
48+2/5-8=
40+2/5=40 2/5
200/5+2/5=202/5=40 2/5


Functions/468600: Can you tell me the steps to solve: Find f(-3) when f(x)=|x-9| Thanks!
1 solutions

Answer 321535 by rfer(12657) About Me  on 2011-07-09 12:01:25 (Show Source):
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f(-3)=|-3-9|
f(-3)=|12|
absolute is value only


Evaluation_Word_Problems/468572: A table is to be sold at P8,500.00. At what price should it be listed to allow a discount series of 15%, 8% and 3%?
1 solutions

Answer 321534 by rfer(12657) About Me  on 2011-07-09 11:58:51 (Show Source):
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8500*0.85=7225*0.92=6647*0.97=$6447.59


Evaluation_Word_Problems/468573: Company A offers to deliver an order of goods at a list price of P54,000.00 less 12%, 7% and 4% discounts. Company B offers to deliver similar goods at the same list price less 15%, 5% and 3% discounts.
a. Which company has the better offer?
b. How much would be saved by taking advantage of the better offer?
1 solutions

Answer 321531 by rfer(12657) About Me  on 2011-07-09 11:50:07 (Show Source):
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Co A
54000*0.88=47520*0.93=44193.60*42425.86
Co B
54000*0.85=45900*0.95=43605*0.97=42296.85
----------------------
Co B best price.
----------------
2nd part
savings=129.01


percentage/468551: in the examination,52% of the candidates failed in english,42% in mathematics.17% failed in both.find the % of those,who pass in both subjects
1 solutions

Answer 321530 by rfer(12657) About Me  on 2011-07-09 11:43:33 (Show Source):
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35% failed just english
25% failed just math
=60% failed at least one.
40% passed both


test/468580: Use the given conditions to write an equation for the lone in point-slope form slope=6/7, passing through (7,3)
1 solutions

Answer 321527 by rfer(12657) About Me  on 2011-07-09 11:29:28 (Show Source):


Linear-equations/468586: Determine whether the given ordered pair is a solution of the system.
(4, 5)
x + y = 9
x - y = -1
1 solutions

Answer 321523 by rfer(12657) About Me  on 2011-07-09 11:20:54 (Show Source):
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4+y=9
y=9-4
y=5
(4,5) ok
--------------
4-y=-1
-y=-5
y=5
(4,5) ok


Exponential-and-logarithmic-functions/468588: Solve the exponential equation. Use a calculator to obtain a decimal approximation, correct to two decimal places, for the solution.
10x = 3.76

1 solutions

Answer 321522 by rfer(12657) About Me  on 2011-07-09 11:18:39 (Show Source):
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10x=3.76
x=3.76/10
x=0.376
x=0.38


Average/468463: solve grade average a student scores 75 and 91 on two differnt tests of 100 points. if the maximum score on the next test is also 100 points, what score does the student need to maintain an average of at least 80?
1 solutions

Answer 321479 by rfer(12657) About Me  on 2011-07-08 23:56:19 (Show Source):
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(75+91+x)/3=80
166+x=80*3
166+x=240
x=74


Number-Line/468519: what is the answer using number line in this equation, (3x-2)=4?
1 solutions

Answer 321477 by rfer(12657) About Me  on 2011-07-08 23:51:43 (Show Source):
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3x-2=4
3x=6
x=2


test/468520: What is 4 and 4/5 divided by 8/15? Can you show work please. Thank you!!
1 solutions

Answer 321476 by rfer(12657) About Me  on 2011-07-08 23:50:32 (Show Source):
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(4 4/5)/(8/15)
24/5*15/8=360/40=9


Volume/468480: what is the volume of the cone with a diameter of 8 inches
1 solutions

Answer 321469 by rfer(12657) About Me  on 2011-07-08 22:48:46 (Show Source):
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not enough information


Polynomials-and-rational-expressions/468499: add (13/10r)+(11/4r)
1 solutions

Answer 321468 by rfer(12657) About Me  on 2011-07-08 22:47:09 (Show Source):
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26/20r+55/20r=81/20r=4 1/20r


Linear-equations/468497: Please help me with this question. Thanks in advance.
An equation and two ordered pairs are given. Show each pair is a solution of the equation, then graph the two pairs to determine another solution.
y = x - 2; (3,1),(- 2,- 4)
1 solutions

Answer 321466 by rfer(12657) About Me  on 2011-07-08 22:45:19 (Show Source):
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y=3-2
y=1
(3,1)
-----------
y=-2-2
y=-4
(-2,-4)


Miscellaneous_Word_Problems/468493: traffic signs are regulated by the manual on uniform traffic control devices. the perimeter of some traffic sign must be 88 inches. also, its length is 6 inches longer than its width. find the dimensions of this sign.
1 solutions

Answer 321465 by rfer(12657) About Me  on 2011-07-08 22:42:23 (Show Source):
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2x+2(x+6)=88
You do the math.
Bob


Rate-of-work-word-problems/468374: The sum of the Three Numbers is 55. The second number is twice the first number, and the third number is three more than one-third the sum of the first two numbers. What are the numbers?
1 solutions

Answer 321426 by rfer(12657) About Me  on 2011-07-08 18:59:58 (Show Source):
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x+2x+1/3(3x)+3=55
4x=52
x=13
2x=26
1/3(3x)+3=16


Money_Word_Problems/468346: The amount of money that a salesperson makes varies directly as the total amount of sales made. If the salesperson receives $7,500 for selling a house for $120,000 how much will he or she make if he or she sells a house for $150,000. So far my answer is 9,375 but I'm not sure I'm doing the work right.
1 solutions

Answer 321424 by rfer(12657) About Me  on 2011-07-08 18:55:56 (Show Source):
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7500/120000=0.0625=6.25%
150000*0.0625=$9375
Looks good to me.
Bob


Volume/468433: Please Help!
Solve the problem. Use = 3.14 when necessary.
At $3.40 per in3, how much will it cost to fill an aquarium with dimensions of 6 1/3 inch x 3 4/5 inch x 4 1/2 inch?

A. $613.70
B. $261.63
C. $368.22
D. $310.94
The answer is C. What are the steps to figure this out. I converted each faction: 6 1/3= 19/3=190/30; 3 4/5= 19/5=114/30; 4 1/2= 9/2=135/30.
Total: 439/30. I am confusing myself.
1 solutions

Answer 321421 by rfer(12657) About Me  on 2011-07-08 18:50:14 (Show Source):
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19/3*19/5*9/2=3249/30 cu in
=108 3/10 cu in total
3249/30*3.40=$368.22
Your working to hard, you need improper fractions to multiply, but no need for common denominators in multiplcaton.
Also to find cubic measurments, multiply not add.
V=L*W*H


Travel_Word_Problems/468373: The speed of train A is 8mph slower than the speed of train B. Train A travels 230 miles in the same time it takes Train B to travel to 270 miles. find the speed of each
1 solutions

Answer 321417 by rfer(12657) About Me  on 2011-07-08 18:42:14 (Show Source):
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230/(x-8)=270/x
230x=270(x-8)
230x=270x-2160
-40x=-2160
x=54 mph
x-8=46 mph


Quadratic_Equations/468067: Identify the vertex and the y-intercept of the graph of each function for y = (x - 125)2 + 125
1 solutions

Answer 321247 by rfer(12657) About Me  on 2011-07-07 20:49:47 (Show Source):
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vertex and y int are the same point
(0,15625)


Inequalities/468179: the smiths have saved $25,000 toward the purchase of a new car. if the sales tax if 5 % the purchase price of the smiths new car before
taxes cannot exceed what ?
1 solutions

Answer 321244 by rfer(12657) About Me  on 2011-07-07 20:39:00 (Show Source):
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25000/1.05=$23,809.52


Coordinate-system/468174: graph: y=4x+80, y=1/2x+10
where do they intercept?
1 solutions

Answer 321241 by rfer(12657) About Me  on 2011-07-07 20:37:23 (Show Source):
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1/2x+10=4x+80
-3.5x=70
x=-20
-------------
y=4*-20+80
y=-80+80
y=0
-----------
intercept (-20,0)
----------------
0=1/5*-20+10


Inequalities/468176: a jewelry salesman can earn either a salary of 2,500 a month or
a salary of 1,000 a month plus 10% of all sales .how much does
he have to sell for the second choice to earn him more than the
first choice ?
1 solutions

Answer 321237 by rfer(12657) About Me  on 2011-07-07 20:30:43 (Show Source):
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1500/0.1=$15,000


Functions/468159: Please I need hel

dipalma uivesity has a faculity reduction and lost 1/14 of its faculityu If 286 of it faculity was left after the reduction how many was there orginally.
1 solutions

Answer 321231 by rfer(12657) About Me  on 2011-07-07 20:00:09 (Show Source):
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286/(13/14)=
286*14/13=308


Evaluation_Word_Problems/468071: The pitch of a roof is the ratio of the rise to the half-span. If a roof has a rise of 6 feet and a span of 30 feet, what is the pitch?

1 solutions

Answer 321213 by rfer(12657) About Me  on 2011-07-07 18:46:07 (Show Source):
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6/30=1/5
one ft rise in five ft run


Systems-of-equations/468135: 2x+7-3x=-x+12
1 solutions

Answer 321211 by rfer(12657) About Me  on 2011-07-07 18:42:15 (Show Source):
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-x+x=5
no solution