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# Recent problems solved by 'rfer'

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 Average/399973: Evaluate -7[-8-(-6)]1 solutions Answer 283283 by rfer(12660)   on 2011-01-26 13:33:50 (Show Source): You can put this solution on YOUR website!-7*-2=+14
 test/400056: Find each sum or difference. (3x2-4x)+(5x2+7x-1) thanks1 solutions Answer 283281 by rfer(12660)   on 2011-01-26 13:27:03 (Show Source): You can put this solution on YOUR website!8x^2+3x-1
 Equations/400065: how do i simplify 9x-18+4x1 solutions Answer 283280 by rfer(12660)   on 2011-01-26 13:25:49 (Show Source): You can put this solution on YOUR website!13x-18
 Money_Word_Problems/400068: The suggested list price of a new car is \$34,000. The dealer's cost is 85% of list. How much will you pay if the dealer is willing to accept \$100 over cost for the car?1 solutions Answer 283279 by rfer(12660)   on 2011-01-26 13:25:16 (Show Source): You can put this solution on YOUR website!34000*0.85+100=29000
 Radicals/399834: How do I solve x^2-15x+56.25=8 by using the square root property? This is what I did: (x^2-15x+56.25=8)/.25 4x^2-60x+225=32 (2x-30)(2x-30) Now I'm stuck and I don't even think I did it right. 1 solutions Answer 283145 by rfer(12660)   on 2011-01-26 00:30:24 (Show Source): You can put this solution on YOUR website!x-3.9x+7.5=2.8 -2.9x=-4.7 x=1.62
 Numeric_Fractions/399840: How do you solve n-5/8=2/5; n= ?1 solutions Answer 283143 by rfer(12660)   on 2011-01-26 00:24:34 (Show Source): You can put this solution on YOUR website!n=5/8+2/5 n=25/40+16/40 n=41/40= 1 1/40
 Expressions-with-variables/399845: 5 + m/7 = 101 solutions Answer 283141 by rfer(12660)   on 2011-01-26 00:22:38 (Show Source): You can put this solution on YOUR website!m/7=5 m=5*7 m=35
 Angles/399829: what is the value of n devided by 4 1/2 when n = 2 2/5 1 solutions Answer 283140 by rfer(12660)   on 2011-01-26 00:21:26 (Show Source): You can put this solution on YOUR website! 2 2/5 / 4 1/4 12/5*4/17=48/85
 Probability-and-statistics/399855: a group of 500 students take a placement test, one particular student scores higher than 350 of the other students, what percentile is that students score?1 solutions Answer 283138 by rfer(12660)   on 2011-01-26 00:16:58 (Show Source): You can put this solution on YOUR website!70th percentile
 decimal-numbers/399869: based on speed, what is the average of 222.089mph, 221.991mph, 220.213mph? round to the nearest thousandth if necessary. I dont know the formula to solve1 solutions Answer 283137 by rfer(12660)   on 2011-01-26 00:13:21 (Show Source): You can put this solution on YOUR website!(222.089+221.991+220.213)/3=
 Numeric_Fractions/399850: What is 5 1/4 - 2 9/16?1 solutions Answer 283136 by rfer(12660)   on 2011-01-26 00:11:33 (Show Source): You can put this solution on YOUR website!5 1/4 - 2 9/16 4 20/16 - 2 9/16=2 11/16
 Rectangles/399867: The area of a rectangle is 3x + 12, and the width is 3. Which expression best describes the rectangle's length? 1 solutions Answer 283135 by rfer(12660)   on 2011-01-26 00:08:53 (Show Source): You can put this solution on YOUR website!L=(3x+12)/3
 Travel_Word_Problems/399870: How long would it take to drive 368 miles at 55 mph?1 solutions Answer 283134 by rfer(12660)   on 2011-01-26 00:07:39 (Show Source): You can put this solution on YOUR website!t=D/r t=368/55 t=6.64 hrs= 6 hrs 38 min
 Coordinate-system/399904: determine whether 2 is a solution of the inequality x>-21 solutions Answer 283133 by rfer(12660)   on 2011-01-26 00:04:30 (Show Source): You can put this solution on YOUR website!x is greater than -2 so yes is a solution.
 Linear-equations/399900: For some reason I am having a hard time figuring out 5>5-7y please help!1 solutions Answer 283132 by rfer(12660)   on 2011-01-26 00:03:37 (Show Source): You can put this solution on YOUR website!y < 0
 Percentage-and-ratio-word-problems/399908: At Central Park Zoo, the ratio of sea lions to penguins is 4:11. If there are 84 more penguins than sea lions, how many sea lions are there? Thank you!!!1 solutions Answer 283131 by rfer(12660)   on 2011-01-26 00:02:01 (Show Source): You can put this solution on YOUR website!4/x=11/84+x 11x=336+4x 6x=336 x=56 sea lions 84+x=140 penguins
 Money_Word_Problems/399907: A principal of \$3200 is invested at 4% interest, compounded annually. How much will the investment be worth after 6 years?1 solutions Answer 283130 by rfer(12660)   on 2011-01-25 23:58:44 (Show Source): You can put this solution on YOUR website!A=3200(1.04)^6 A=4049
 Coordinate-system/399905: from a base elevation of 8500 ft a mountain peak in colorado rises to a summit elevation of 14350 ft over a horizontal distance of 15842 ft, find the grade of the peak in %1 solutions Answer 283129 by rfer(12660)   on 2011-01-25 23:57:16 (Show Source): You can put this solution on YOUR website!5850/15842=37%
 Numbers_Word_Problems/399712: I typed my email address wrong on my last question. 4th grade grandson has a question on his homework. Something like this--Joe had 7 more pencils than Jack, and they had 29 in all. How many did each boy have? I said 11 + 18 but I don't know how to tell him how to find the answer. Can you give me steps or an equation to show how to find the answer?1 solutions Answer 283036 by rfer(12660)   on 2011-01-25 18:48:33 (Show Source): You can put this solution on YOUR website!?+?+7=29 2*?=22 divide 22 by 2 ?=11 ?+7=18 I used question makes for the unknown amounts almost like setting up an algebra problem.
 Equations/399698: (3x+7)^21 solutions Answer 283034 by rfer(12660)   on 2011-01-25 18:44:20 (Show Source): You can put this solution on YOUR website!(3x+7)(3x+7) 9x^2+21x+21x+49 9x^2+42x+49
 Equations/399648: The area of triangle with base, b and height h, is given by:a=1/2bh If the area of a certain trangle is 46 square inches and the height is 20 inches, what is the base? Please show all of your work. MAY I HAVE ASSISTANCE PLZ!!!1 solutions Answer 282993 by rfer(12660)   on 2011-01-25 17:36:21 (Show Source): You can put this solution on YOUR website!46=0.5*b*20 46=10b b=46/10 b=4.6
 Expressions-with-variables/399658: How do you solve: 5x + 24 = 8x1 solutions Answer 282991 by rfer(12660)   on 2011-01-25 17:32:33 (Show Source): You can put this solution on YOUR website!24=3x x=24/3 x=8
 Evaluation_Word_Problems/399657: So,im learning how to do Two-step problem such as substitution heres my question F=9/5(-20)+32 I have to convert the temperature to degrees fahreheit!1 solutions Answer 282990 by rfer(12660)   on 2011-01-25 17:31:39 (Show Source): You can put this solution on YOUR website!F=-180/5+32 F=-36+32 F=-4 degrees
 Expressions-with-variables/399655: Solve for t+14>51 solutions Answer 282988 by rfer(12660)   on 2011-01-25 17:29:46 (Show Source): You can put this solution on YOUR website!t > -9
 Numeric_Fractions/399656: I am having trouble with equations in fractions with a variable, can you help? a-1/6=-2/31 solutions Answer 282987 by rfer(12660)   on 2011-01-25 17:29:11 (Show Source): You can put this solution on YOUR website!a=-2/3+1/6 a=-4/6+1/6 a=-3/6 a=-1/2
 Mixture_Word_Problems/399625: sprockets R Us is selling its bicycle sprockets for 2/5 of a dollar. this price shows a decrease of 1/3 of the original price. what was the original price?1 solutions Answer 282986 by rfer(12660)   on 2011-01-25 17:27:44 (Show Source): You can put this solution on YOUR website!(2/5)/(2/3) 2/5*3/2=6/10=\$0.60 .40/2/3= 0.40*3/2=\$0.60
 Quadratic_Equations/399614: 12x²=2161 solutions Answer 282985 by rfer(12660)   on 2011-01-25 17:22:24 (Show Source): You can put this solution on YOUR website!12x^2=216 x^2=216/12 x^2=18 x=4.24
 Rectangles/399639: A rectangle has a perimeter of 28 cm. What is the maximum area for the rectangle?1 solutions Answer 282984 by rfer(12660)   on 2011-01-25 17:20:23 (Show Source): You can put this solution on YOUR website!28/4=7 7^2=49 sq cm
 Average/399327: how do i figure/find the average of -10, 8, -4, 2, 7, -5, -121 solutions Answer 282759 by rfer(12660)   on 2011-01-24 23:54:58 (Show Source): You can put this solution on YOUR website!-14/7=-2
 Expressions-with-variables/399295: The perimeter of a square is 42 feet and the sides of the square are each s ft; set up the equation expressing this. 1 solutions Answer 282758 by rfer(12660)   on 2011-01-24 23:52:34 (Show Source): You can put this solution on YOUR website!s=p/4 s=42/4 s=10.5 ft each side
 test/399303: x - 22 divided by 5 = 81 solutions Answer 282756 by rfer(12660)   on 2011-01-24 23:50:34 (Show Source): You can put this solution on YOUR website!x-4.4=8 x=12.4