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Recent problems solved by 'rfer'

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Polynomials-and-rational-expressions/317993: 2+8y=9y 1 solutions Answer 227677 by rfer(12731)   on 2010-06-27 17:56:26 (Show Source): You can put this solution on YOUR website! y=2

Equations/317733: What is the answer to x=5y, 2x-3y=7? 1 solutions Answer 227591 by rfer(12731)   on 2010-06-26 21:56:49 (Show Source): You can put this solution on YOUR website! 2(5y)-3y=7 10y-3y=7 7y=7 y=1

Travel_Word_Problems/317803: A car traveled at an averge speed of 50 miles per hour for a trip of 225 miles . how long did the trip take ? 1 solutions Answer 227590 by rfer(12731)   on 2010-06-26 21:53:16 (Show Source): You can put this solution on YOUR website! 225/50=4.5 hrs

Equations/317807: Please help me with this: Write the slope-intercept form of the line that passes through the given point with slope M. Through (-1,-4), m=-3 Thank you . 1 solutions Answer 227588 by rfer(12731)   on 2010-06-26 21:52:22 (Show Source): You can put this solution on YOUR website! y=-3x-7

Square-cubic-other-roots/317576: I need to know how to simplify this equation (16)3/4 I need this broke down step by step so i understand how to do it. 1 solutions Answer 227447 by rfer(12731)   on 2010-06-25 21:38:18 (Show Source): You can put this solution on YOUR website! you are multiplying 16 times 3/4 then reduce same as 16/1*3/4=48/4=12

Travel_Word_Problems/317570: Two trains leave towns 1332 km apart at the same time and travel toward each other. One train travels 20 km/hr slower than the other. If they meet in 6 hours, what is the rate of each train? 1 solutions Answer 227443 by rfer(12731)   on 2010-06-25 21:34:36 (Show Source): You can put this solution on YOUR website! x*6+(x-20)*6=1332 6x+6x-120=1332 12x=1452 x=121 kmph x-20=101 kmph

Travel_Word_Problems/317582: If a car travels 60 miles in 45 minutes, how many miles per hour was it going? 1 solutions Answer 227441 by rfer(12731)   on 2010-06-25 21:30:48 (Show Source): You can put this solution on YOUR website! 60/.75=80 mph

Travel_Word_Problems/317588: The sum of two numbers is 60 . One number is 4 times as large as the other. What are the numbers? 1 solutions Answer 227440 by rfer(12731)   on 2010-06-25 21:28:05 (Show Source): You can put this solution on YOUR website! x+4x=60 5x=60 x=12 4x=48

Polynomials-and-rational-expressions/317593: collect like terms x-7x 1 solutions Answer 227439 by rfer(12731)   on 2010-06-25 21:26:35 (Show Source): You can put this solution on YOUR website! -6x

Coordinate-system/317605: coordinates for the x and y intercepts for the equation 3x+2y=30 1 solutions Answer 227437 by rfer(12731)   on 2010-06-25 21:25:28 (Show Source): You can put this solution on YOUR website! 3(0)+2y=30 2y=30 y=15 (0,15) 3x+2(0)=30 3x=30 x=10 (10,0)

Human-and-algebraic-language/317628: Can someone please help! I need to solve for 'w' but i dont know how to solve it, can someone show me the steps on how to solve. (2/8)+(3/4)= (w/6) 1 solutions Answer 227436 by rfer(12731)   on 2010-06-25 21:20:32 (Show Source): You can put this solution on YOUR website! 2/8+3/4=w/6 2/8+6/8=w/6 8/8=w/6 8/8=1 1=w/6 1*6=w 6=w

Linear_Equations_And_Systems_Word_Problems/317298: Consider the formula F(c) = 1.8c + 32, where c is the temperature in degrees Celsius and F(c) is the temperature in degrees Fahrenheit. If it is 0° C at the beginning of the day, and it is 11° C at noon, what was the change in temperature in degrees Fahrenheit? 1 solutions Answer 227400 by rfer(12731)   on 2010-06-25 14:56:27 (Show Source): You can put this solution on YOUR website! F=1.8*11+32 F=51.8 degrees 51.8-32=19.8 degrees change F

percentage/317289: If the posted fee to cash a check is 10% and you charge 5%, what percent discount did you give? 1 solutions Answer 227398 by rfer(12731)   on 2010-06-25 14:53:37 (Show Source): You can put this solution on YOUR website! 50%

Average/317529: A company that produces bicycles has costs given by the function C(x)=25x+20000, where x is the number of bikes manufactured and C(x) is measured in dollars. The average cost to manufacture each bike is given by C(x)=(25(x)+20000)/x. Find C(250) and round to the nearest dollar, if necessary. The choices are $33, $135, $105, and $30. I believe this is an "average cost function" question, but no matter what I do to solve this question, I don't get any of these answers. Ken 1 solutions Answer 227397 by rfer(12731)   on 2010-06-25 14:49:20 (Show Source): You can put this solution on YOUR website! answer is $105 c(x)=(25(250)+20000)/250

Surface-area/317347: how do i find the appropriate formula to find the surface area of the room 9ft x 12ft? 1 solutions Answer 227216 by rfer(12731)   on 2010-06-24 20:59:47 (Show Source): You can put this solution on YOUR website! A=L*W A=9*12 A=108 sq ft

Probability-and-statistics/317258: Evaluate: 4C0 1 solutions Answer 227207 by rfer(12731)   on 2010-06-24 20:31:27 (Show Source): You can put this solution on YOUR website! 4C0=0

Geometry_Word_Problems/317315: the smallest angle in a triangle is 1/5 as large as the largest angle. the third angle is twice the smallest angle. find the three angles. 1 solutions Answer 227206 by rfer(12731)   on 2010-06-24 20:30:18 (Show Source): You can put this solution on YOUR website! .2x+x+2*.2x=180 1.6x=180 x=112.5 degrees .2x=22.5 degrees 2*.2x=45 degrees

Linear_Equations_And_Systems_Word_Problems/317014: Solve the following problem. Be sure to show all steps (V.E.S.T.) The sum of three numbers is 26. The second number is twice the first and the third number is 6 more than the second. Find the numbers. 1 solutions Answer 226980 by rfer(12731)   on 2010-06-23 21:15:36 (Show Source): You can put this solution on YOUR website! x+2x+2x+6=26 5x=20 x=4 2x=8 2x+6=14

Miscellaneous_Word_Problems/317030: rebekah recipe for 4 1/2 dozen cookies calls for 6 cups of sugar. how many cups of sugar are needed to make 8 dozen cookies? 1 solutions Answer 226978 by rfer(12731)   on 2010-06-23 21:12:42 (Show Source): You can put this solution on YOUR website! 4.5/6=8/x 4.5x=48 x=10.7 cups

Angles/316809: 1.find the measure of 2 complementary angles such that the larger angle is six less then five times the smaller angle. 2.Find the measure of the larger angle of 2 complementary angles such that one half of the larger is 15 more than one-fourth the smaller angle 1 solutions Answer 226810 by rfer(12731)   on 2010-06-23 12:17:28 (Show Source): You can put this solution on YOUR website! 1) x+5x-6=90 6x=96 x=16 degrees 5x-6=74 degrees

Expressions-with-variables/316846: 6-2(5x-8)=3x-4 1 solutions Answer 226809 by rfer(12731)   on 2010-06-23 12:13:39 (Show Source): You can put this solution on YOUR website! 6-2(5x-8)=3x-4 6-10x+16=3x-4 -13x=-26 x=2

Numeric_Fractions/316401: 2/3+1/3(2 1/2+1/2)square 2 3/8 + 1/2(1/3+5/3)exponent of3 1 solutions Answer 226682 by rfer(12731)   on 2010-06-22 21:45:20 (Show Source): You can put this solution on YOUR website! 2/3+1/3(2 1/2+1/2)^2 2/3+1/3(3)^2 2/3+3 2/3+9/3=11/3=3 1/3 -------------------- 2 3/8+1/2(1/3+5/3)^3 2 3/8+1/2(6/3)^3 2 3/8+1/2*27 2 3/8+13 1/2 51/24+324/24 375/24=15 5/8

Mixture_Word_Problems/316457: A discount store takes 50% off of the retail price of a desk. Fo the store's holiday sale, it takes an additional 20% off of all furniture.The desk's retail price was $320. How much is th desk on sle for during the holiday sale? 1 solutions Answer 226678 by rfer(12731)   on 2010-06-22 21:37:19 (Show Source): You can put this solution on YOUR website! 320*.5=160 160*.8=$128

Equations/316567: 12/5x+7=31-3/5x -2x+5x-9=3(x-4)-5 -5/6x=-15 6=x/7 4/5x=-15 1 solutions Answer 226677 by rfer(12731)   on 2010-06-22 21:32:09 (Show Source): You can put this solution on YOUR website! 12/5x+7=31-3/5x 15/5x=24 5x=1.6 x=0.32 ==========

Money_Word_Problems/316679: Find the lump sum deposited today that will yield the same total amount as payments of $10,000 at the end of each year for 15 years at 4% compounded annually. 1 solutions Answer 226676 by rfer(12731)   on 2010-06-22 21:26:53 (Show Source): You can put this solution on YOUR website! P=(1+.04)^15/10000 P= 10000/(1.04)^15 P=10000/1.8 P=5555.56

Angles/316726: 2.Find the measure of the supplement of an angle that measures 72° 1 solutions Answer 226671 by rfer(12731)   on 2010-06-22 21:21:54 (Show Source): You can put this solution on YOUR website! 180-72=108 degrees

Linear-equations/316725: hi. my name is brandie and i really need help in math.my question is how do i solve algebric eqations and how do you find the slop of a line im going to the tenth grade please elp 1 solutions Answer 226670 by rfer(12731)   on 2010-06-22 21:21:07 (Show Source): You can put this solution on YOUR website! The best thing I can tell you is to get the GED math book and work through that section. All the answers are in the book.

Rectangles/316722: if two planes leave an airport at the same time with one flying west at 530 miles per hour and the other flying east at 620 miles per hour, how long will it take them to be 5750 miles apart? 1 solutions Answer 226668 by rfer(12731)   on 2010-06-22 21:19:30 (Show Source): You can put this solution on YOUR website! moving apart at 1150 mph 5750/1150=5 hrs

Miscellaneous_Word_Problems/316696: Consider the followinglist of test scores: 98,70,32,48,71,80,85,50,46,71. For this data, find each of the following. Round to nearest tenth when necessary. (a) the mean (b) The median (c) The mode (d) The range 1 solutions Answer 226666 by rfer(12731)   on 2010-06-22 21:17:55 (Show Source): You can put this solution on YOUR website! a=65.1 b=70.5 c=71 d=66

Inequalities/316717: 2 - x < 4 1 solutions Answer 226659 by rfer(12731)   on 2010-06-22 21:11:51 (Show Source): You can put this solution on YOUR website! x > -2

Geometry_Word_Problems/316463: The width of a rectangle is fixed at 24 cm. What lengths will make the perimeter greater than 88 cm? 1 solutions Answer 226621 by rfer(12731)   on 2010-06-22 18:47:39 (Show Source): You can put this solution on YOUR website! 88-48=40/2>20 cm