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Recent problems solved by 'rfer'

rfer answered: 12727 problems
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test/457447: Two cars leave the same place at the same time traveling in opposite directions. One car is traveling at a rate of 30 mph while the other is traveling at a rate of 45 mph. How long will it take until the cars are 250 miles apart? 1 solutions Answer 313845 by rfer(12731)   on 2011-06-04 18:28:54 (Show Source): You can put this solution on YOUR website! moving apart at 75 mph 250/75=3 hrs 20 min

Graphs/457219: I need your help on this question Sketch the graph of the relation 3x + 2y = 8 by finding four ordered pairs which satisfy this relation. Thanks... 1 solutions Answer 313714 by rfer(12731)   on 2011-06-03 21:15:55 (Show Source): You can put this solution on YOUR website! make an input/output table 3*0+2y=8 y=4 (0,4) ----------- 3*2+2y=8 6+2y=8 y=1 (2,1) ------------ 3*3+2y=8 9+2y=8 y=-1/2 (3,1/2) ------------ 3*6+2y=8 18+2y=8 2y=-10 y=-5 (6,-5)

Linear-equations/457213: Multiply 3x(-x+8) 1 solutions Answer 313712 by rfer(12731)   on 2011-06-03 20:57:36 (Show Source): You can put this solution on YOUR website! -3x^2+24x

Age_Word_Problems/457217: A women is five times as old as her grandson. If she is sixty years older than the boy, what are their ages? 1 solutions Answer 313711 by rfer(12731)   on 2011-06-03 20:56:17 (Show Source): You can put this solution on YOUR website! 15 and 75

Money_Word_Problems/457204: Money in a saving account increases at a rate of 4% per year. If the account has $22,000 in it now, how much should it have at the end of 2 years? 1 solutions Answer 313694 by rfer(12731)   on 2011-06-03 19:31:05 (Show Source): You can put this solution on YOUR website! A=22000(1.04)^2 A=$23,795.20

Surface-area/457179: a square room has a floor area of 150 square feet. which number is closet to the length of one side of the room 1 solutions Answer 313668 by rfer(12731)   on 2011-06-03 17:28:49 (Show Source): You can put this solution on YOUR website! sqrt 150=12.25 ft

Money_Word_Problems/457171: Find the simple interest on a $700 loan for 45 days at a 15% rate of interest please. 1 solutions Answer 313667 by rfer(12731)   on 2011-06-03 17:21:35 (Show Source): You can put this solution on YOUR website! I=Prt I=700*0.15*45/365 I=$12.95

Polynomials-and-rational-expressions/457071: A textbook costs a bookstore $56, and the store sells it for $70. Find the rate of profit based on the selling price. 1 solutions Answer 313641 by rfer(12731)   on 2011-06-03 13:43:57 (Show Source): You can put this solution on YOUR website! 70-56=14 14/70=0.2=20%

Inequalities/457102: Translate to an inequality. The maximum safe exposure limit of formaldehyde is 2 parts per million. 1 solutions Answer 313640 by rfer(12731)   on 2011-06-03 13:41:36 (Show Source): You can put this solution on YOUR website! e=<2/1.0x10^6

Expressions-with-variables/457098: After being discounted 45%, a radio sells for $49.20. Find the original price. 1 solutions Answer 313639 by rfer(12731)   on 2011-06-03 13:39:16 (Show Source): You can put this solution on YOUR website! 49.20/0.55=$89.45

Age_Word_Problems/457094: If I have 3 years and my brother is 3 years older than me. How old is my brother? 1 solutions Answer 313638 by rfer(12731)   on 2011-06-03 13:37:58 (Show Source): You can put this solution on YOUR website! 6 yrs

Expressions-with-variables/457099: Some bank robbers leave town, speeding at 71 mph. Twelve minutes later, the police give chase, traveling at 80 mph. How long will it take after the robbery for the police to overtake the robbers? 1 solutions Answer 313637 by rfer(12731)   on 2011-06-03 13:37:16 (Show Source): You can put this solution on YOUR website! 14.2 mi lead overtake speed=9mph 14.2/9=1.6 hrs =1 hr 36 min

Linear-equations/457100: What is the slope of the line between (-4, 4) and (-1, -2) 1 solutions Answer 313635 by rfer(12731)   on 2011-06-03 13:34:48 (Show Source): You can put this solution on YOUR website! slope m=(-2-4)/(-1--4) m=-6/3 m=-2

Evaluation_Word_Problems/457078: i need help solving this problem: (3-4((-2)+h)^2)-(3-4((-2)^2)/h the answer is (16h-4h^2)/(h) my question is how did they get to the answer? If you could please show me a step by step instruction on how to solve this problem i would greatly appreciate it. thank you. 1 solutions Answer 313634 by rfer(12731)   on 2011-06-03 13:33:11 (Show Source): You can put this solution on YOUR website! I am doing this in two parts (3-4((-2+h)^2) (3-4(+4-4h+k^2 3-16+16h-4h^2 ---------------- -(3-4((-2)^2)/h -(3-16)/h +13/h ------------------ 3-16+16h-4h^2+13/h -13+16h-4h^2+13/h the two 13's cancel (+16h-4h^2)/h I hope that helps Bob

Money_Word_Problems/457076: If you invest $5,550.00 in an account for 5 years that earns an annual rate of 6.50% compounded quarterly, what is the future value? 1 solutions Answer 313632 by rfer(12731)   on 2011-06-03 13:16:56 (Show Source): You can put this solution on YOUR website! FV=5550(1+0.065/4)^4*5 FV=5550(1.01625)^20 FV=5550*1.38 FV=$7659.00

Exponents/457064: 6.334 * 10^4 I just wanted another set of eyes to check over my work. I did 10*10=100, then 100*10=1000, then 1000*10=10000 Then 10000*6.334=63340. 1 solutions Answer 313612 by rfer(12731)   on 2011-06-03 10:55:13 (Show Source): You can put this solution on YOUR website! Your answer is correct, but this is a powers of 10 problem. All you have to do is move the decimal 4 places to the right. If you had a minus exponent you would move the decimal to the left.

Polynomials-and-rational-expressions/456985: Find the following product (y-3)^2 (y-3) (y-3) y^2-6y+9 Is this question correct? Will someone please check, Thank you 1 solutions Answer 313610 by rfer(12731)   on 2011-06-03 10:52:08 (Show Source): You can put this solution on YOUR website! Looks good to me. Have a good day. Bob

Equations/457056: 6 3/4 x 5 1/3 also i dont really understand the steps and why you do them 1 solutions Answer 313606 by rfer(12731)   on 2011-06-03 10:41:20 (Show Source): You can put this solution on YOUR website! this is streight multiplication 6 3/4 x 5 1/3 27/4*16/3=432/12=36

Numeric_Fractions/457059: what is the sum of the fractions 3/8 and 1/16? 1 solutions Answer 313604 by rfer(12731)   on 2011-06-03 10:37:51 (Show Source): You can put this solution on YOUR website! 6/16+1/16=7/16

Money_Word_Problems/456950: You deposit $500 in account paying 4.5% interest compounded annually. Find the dollar value of the account rounded to the nearest penny after 10 years. 1 solutions Answer 313558 by rfer(12731)   on 2011-06-02 23:18:21 (Show Source): You can put this solution on YOUR website! A=500(1.045)^10 A=$776.48

Equations/456907: what is 10+3(5a-5a)+10a+3 1 solutions Answer 313544 by rfer(12731)   on 2011-06-02 21:54:24 (Show Source): You can put this solution on YOUR website! =10a+13

Triangles/456930: In a triangle, the ratio of the measures of the sides is 2:3:4 and the perimeter is 144. Find the measures of the sides on the triangle. 1 solutions Answer 313542 by rfer(12731)   on 2011-06-02 21:52:16 (Show Source): You can put this solution on YOUR website! 2x+3x+4x=144 9x=144 x=16 2x=32 3x=48 4x=64

Linear-equations/456822: Find an equation of the line having the given slope and containing the given point. m = 8/9, (3, -5) 1 solutions Answer 313490 by rfer(12731)   on 2011-06-02 19:51:52 (Show Source): You can put this solution on YOUR website! y=8/9x-2.5

Miscellaneous_Word_Problems/456876: v/-3=6 1 solutions Answer 313489 by rfer(12731)   on 2011-06-02 19:49:16 (Show Source): You can put this solution on YOUR website! v=6*-3 v=-18

Pythagorean-theorem/456848: how to solve a multi step equations 1 solutions Answer 313482 by rfer(12731)   on 2011-06-02 19:04:59 (Show Source): You can put this solution on YOUR website! one step at a time.

Volume/456864: how do you determine the volume of each soild figure 1 solutions Answer 313481 by rfer(12731)   on 2011-06-02 18:59:38 (Show Source): You can put this solution on YOUR website! V=lwh or V=pir^h

Volume/456865: I am trying to find the volume of a capsule. I am only given the length and width. The length is not the length of the cylinder between the two hemispheres of the capsule. It is of the entire capsule, from end to end of the capsule. This length is 40 feet. The diameter of the cylinder is 5 feet. That is all the information I am given. Thanks for the help! 1 solutions Answer 313480 by rfer(12731)   on 2011-06-02 18:58:33 (Show Source): You can put this solution on YOUR website! the two endes of the capsule together form a sphere so you can calculate that A=pid^2 A=3.14*5^2 A=78.5 cu ft -------------- The radius of each end is 2.5 ft so subtract 5 from 40=35 the length of the cylinder -------------- Volume of cylinder V=3.14*r^2*h V=3.14*2.5^2*40 V=785 cu ft ----------- Total volume 78.5+785=863.5 cu ft

Rectangles/456861: What is the perimeter of a rectangle that is 12 and 1/3 yd long and 5 2/3 yd wide? 1 solutions Answer 313479 by rfer(12731)   on 2011-06-02 18:49:28 (Show Source): You can put this solution on YOUR website! 2*12.33+2*5.66= 24.6+11.32=35.92 sq yds

Rational-functions/456654: In the equation x/(x - 6) = 1/(x - 4) why is it true that your solution could never be x = 6 or x = 4? 1 solutions Answer 313380 by rfer(12731)   on 2011-06-02 11:20:01 (Show Source): You can put this solution on YOUR website! Because the denominators would become zero, you can not divide or multiply by zero

Rectangles/456629: write an equation for the area of a rectangle in terms of one variable with a length 5 inches less than the width. 1 solutions Answer 313379 by rfer(12731)   on 2011-06-02 11:17:32 (Show Source): You can put this solution on YOUR website! A=x(x-5)

Radicals/456675: -3x + 6(-2x - 5) = -40 - 5x 1 solutions Answer 313377 by rfer(12731)   on 2011-06-02 11:15:41 (Show Source): You can put this solution on YOUR website! -3x-12x-30=-40-5x -10x=-10 x=-10/-10 x=+1