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Recent problems solved by 'rfer'

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Inequalities/313108: 145=10x-8x 1 solutions Answer 223971 by rfer(12652)   on 2010-06-10 18:15:29 (Show Source): You can put this solution on YOUR website! 145=10x-8x 145=2x x=72.5

percentage/313221: This is a type of question I do not seem to understand and I definitely need help with this problem: The sales price of a car is $12,590, which is 20% off the original price. What is the original price? 1 solutions Answer 223969 by rfer(12652)   on 2010-06-10 18:12:42 (Show Source): You can put this solution on YOUR website! 12590/.80=$15,737.50

Human-and-algebraic-language/313177: The Andrews are selling their home. They want to keep $150,000 after paying a 7% commission to a realtor. For how much must they sell the house(to the nearest dollar)? 1 solutions Answer 223968 by rfer(12652)   on 2010-06-10 18:11:23 (Show Source): You can put this solution on YOUR website! 150000*1.07=$160,500

Evaluation_Word_Problems/313216: Stephen is traveling for the weekend. His parents sain they would give him $2.50 for each gallon of gas he uses. Since gas costs more than $2.50 a gallon, Stephen needs to put in an extra $30.75 for his trip. If he spent altogether $120.50 on gas, how many gallons of gas did he buy? 1 solutions Answer 223966 by rfer(12652)   on 2010-06-10 18:09:25 (Show Source): You can put this solution on YOUR website! 120.50-30.75=89.75 89.75/2.50=35.9 gal

Linear-equations/312903: Solve 5(r-7)+4 >6(r+2)-24 The solution set is {r|r ___ ___} If someone could please help me with this. I came up with <-19, but I am not sure how I did it - can you show me the work? Thank you so much. 1 solutions Answer 223783 by rfer(12652)   on 2010-06-09 19:54:09 (Show Source): You can put this solution on YOUR website! 5r-35+4>6r+12-24 r < -19 looks good

Distributive-associative-commutative-properties/312894: What is the answer to >>>9x - x - 5 - 1 1 solutions Answer 223781 by rfer(12652)   on 2010-06-09 19:48:32 (Show Source): You can put this solution on YOUR website! 8x-6

Distributive-associative-commutative-properties/312890: What is the answer to >>> 6a - 4 - 2a +6a 1 solutions Answer 223780 by rfer(12652)   on 2010-06-09 19:47:32 (Show Source): You can put this solution on YOUR website! 10a-4

Polynomials-and-rational-expressions/312970: i need this problem factored x^2-3x-40 1 solutions Answer 223777 by rfer(12652)   on 2010-06-09 19:45:14 (Show Source): You can put this solution on YOUR website! (x+5)(x-8)

Money_Word_Problems/312873: an invoice for $450.00 has terms 2/10, 1/30, n/60. if you pay on the eighth day, how much will you remit 1 solutions Answer 223769 by rfer(12652)   on 2010-06-09 19:21:04 (Show Source): You can put this solution on YOUR website! 450*.98=$441

Polynomials-and-rational-expressions/312939: if two numbers differ by 14, then what polynomial represents their product? Let x represent the smaller number 1 solutions Answer 223767 by rfer(12652)   on 2010-06-09 19:18:42 (Show Source): You can put this solution on YOUR website! x(x+14)=

Percentage-and-ratio-word-problems/312948: a shop sells compact discs for $15 per piece. If each disk costs $12 to the shop owner how much profit per cent does ths shop owner earn? 1 solutions Answer 223766 by rfer(12652)   on 2010-06-09 19:17:07 (Show Source): You can put this solution on YOUR website! 3/12=0.25=25%

Equations/312786: -9.9= 6r+14.1 1 solutions Answer 223702 by rfer(12652)   on 2010-06-09 14:04:50 (Show Source): You can put this solution on YOUR website! -9.9=6r+14.1 6r=-24 r=-4

Human-and-algebraic-language/312857: joe has a total of $580 consisting 5$ and 10$ bills. If he has 76 bills in all, how many of each type does he have? 1 solutions Answer 223701 by rfer(12652)   on 2010-06-09 14:02:31 (Show Source): You can put this solution on YOUR website! f+t=76 t=76-f 5f+10(76-f)=580 5f+760-10f=580 -5f=-180 f=36 fives t=76-36 t=40 tens ---------- 400+180=580

Geometry_Word_Problems/312801: Find the width of a circle in feet that has an are of 200sq. Inches 1 solutions Answer 223695 by rfer(12652)   on 2010-06-09 13:51:32 (Show Source): You can put this solution on YOUR website! 16 in try to solve it using A=pir^2

Linear-equations/312802: A line passes through the point (4,-7) and has a slope of -4 . Write an equation for this line. 1 solutions Answer 223693 by rfer(12652)   on 2010-06-09 13:49:51 (Show Source): You can put this solution on YOUR website! y=-4x+6

test/312809: 2b +c2 b=3 c=5 1 solutions Answer 223692 by rfer(12652)   on 2010-06-09 13:47:23 (Show Source): You can put this solution on YOUR website! 2*3+5^2=31

Equations/312805: How would you solve for the indicated letter f=9g you are solving for g 1 solutions Answer 223691 by rfer(12652)   on 2010-06-09 13:46:08 (Show Source): You can put this solution on YOUR website! g=f/9

Linear-equations/312803: How would you find the slope containing the pair of points (4,7) and (8,-1) 1 solutions Answer 223690 by rfer(12652)   on 2010-06-09 13:44:46 (Show Source): You can put this solution on YOUR website! -8/4=m=-2

Equations/312804: How do you find the solution set for -6x>1/3 1 solutions Answer 223689 by rfer(12652)   on 2010-06-09 13:41:58 (Show Source): You can put this solution on YOUR website! -6x > 1/3 x > (1/3)/(-6/1) x > 1/3*-1/6 x > -1/18

Graphs/312815: given that bobs scores were 133,155,176,and 132,find her average score. 1 solutions Answer 223688 by rfer(12652)   on 2010-06-09 13:39:33 (Show Source): You can put this solution on YOUR website! (133+155+176+132)/4=149

Reduction-of-unit-multipliers/312831: Convert 2.3 kilometers / second into miles / hour (1 kilometer = 0.6214 miles). Show your work 1 solutions Answer 223684 by rfer(12652)   on 2010-06-09 13:32:49 (Show Source): You can put this solution on YOUR website! 2.3 k*3600=8280 kph 8280*.6214=5145.92 mph

Quadratic_Equations/312839: How do I evaluate this equation? -3/5[2/3 - 1/2(3/4 - 1/2)]= Thanks 1 solutions Answer 223682 by rfer(12652)   on 2010-06-09 13:29:27 (Show Source): You can put this solution on YOUR website! -3/5[2/3-1/2(3/4-1/2)] follow the order of operations -3/5[2/3-3/8+1/4] -3/5[2/3-1/8] -3/5[16/24-3/24] -3/5*13/24 -39/120=-13/40

Evaluation_Word_Problems/312836: Please assist me in this substution problem & please include the check at the end. 5x-3y=65 x=-2y Thank You! Steve 1 solutions Answer 223679 by rfer(12652)   on 2010-06-09 13:23:49 (Show Source): You can put this solution on YOUR website! 5(-2y)-3y=65 -10y-3y=65 -13y=65 y=-5 ------------- x=-2(-5) x=10 ------------- proof 5(10)-3(-5)=65 50+15=65

Linear-systems/312660: what is 9-x-4x=11 1 solutions Answer 223520 by rfer(12652)   on 2010-06-08 21:33:12 (Show Source): You can put this solution on YOUR website! -5x=2 x=-2/5

Rectangles/312662: What is the radius of a circle with an area of 66.5cm^2? 1 solutions Answer 223518 by rfer(12652)   on 2010-06-08 21:31:35 (Show Source): You can put this solution on YOUR website! 66.5/3.14=21.18 sq rt 21.18=4.6 cm

Proportions/312506: Find the unknown quantity for the following ratios and proportions. If the primary to secondary voltage ratio is 4:1 for a transformer, what is the secondary voltage if the primary voltage is 460 volts? 1 solutions Answer 223492 by rfer(12652)   on 2010-06-08 19:00:00 (Show Source): You can put this solution on YOUR website! 460/4=115 v

Travel_Word_Problems/312519: 2 cans are 33 cents maybe purchase in lots of one dozen for $1.74. What is the saving? 1 solutions Answer 223491 by rfer(12652)   on 2010-06-08 18:58:38 (Show Source): You can put this solution on YOUR website! 1.74/12=14.5 cents each 33/2=16.5 cents each 2 cents savings on each can

Polynomials-and-rational-expressions/312523: A television commercial about cholesterol claimed that by using their pills at least one person lowered his cholesterol by 18%, a drop of 30 points! What was the original cholesterol level? 1 solutions Answer 223490 by rfer(12652)   on 2010-06-08 18:56:39 (Show Source): You can put this solution on YOUR website! 30/.18=167

Equations/312565: 0=5(k+9) 1 solutions Answer 223485 by rfer(12652)   on 2010-06-08 18:40:14 (Show Source): You can put this solution on YOUR website! 0=5(k+9) 0=5k+45 5k=-45 k=-9

Miscellaneous_Word_Problems/312589: How can this problem be simplified? (c-9) -3(c-3) 1 solutions Answer 223484 by rfer(12652)   on 2010-06-08 18:37:46 (Show Source): You can put this solution on YOUR website! (c-9)-3(c-3) c-9-3c+9=-2c

Graphs/312602: 1. You are planning to spend no less than $6,000 and no more than $10,000 on your landscaping project. a. Write an inequality that demonstrates how much money you will are willing to spend on the project. 1 solutions Answer 223483 by rfer(12652)   on 2010-06-08 18:35:27 (Show Source): You can put this solution on YOUR website! 6000 < x < 10000