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rfer answered: 12653 problems
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Money_Word_Problems/237175: a wool siut iscounted by 30% for clearance sale has a price of 399 whats the suit original price? 1 solutions Answer 174429 by rfer(12657)   on 2009-11-09 22:34:53 (Show Source): You can put this solution on YOUR website! 399/.7=$570

Numbers_Word_Problems/237093: the difference of three times a number and seven equals the difference of nine and a number. set up equation and solve 1 solutions Answer 174427 by rfer(12657)   on 2009-11-09 22:33:33 (Show Source): You can put this solution on YOUR website! 3x-7=x-9 2x=-2 x=-1

Linear-systems/237138: How do you solve a system of linear equations if one of the sets only has and x and y, no answer? Example: 5x -7y = 2 3x = 4y 1 solutions Answer 174425 by rfer(12657)   on 2009-11-09 22:25:55 (Show Source): You can put this solution on YOUR website! do you mean x=y if so they are equal in the order pairs x & y are the same number

Numbers_Word_Problems/237106: The difference between two numbers is 3. The sum of the numbers is 45. what are the two numbers? 1 solutions Answer 174424 by rfer(12657)   on 2009-11-09 22:23:13 (Show Source): You can put this solution on YOUR website! x+y=45 x-y=3, x=y+3 --------------- y+3+y=45 2y=42 y=21 ----------------- x-21=3 x=24

Travel_Word_Problems/237170: IF YOU ARE DRIVING 55MPH...HOW LONG WILL IT TAKE TO DRIVE 316 MILES? 1 solutions Answer 174423 by rfer(12657)   on 2009-11-09 22:19:41 (Show Source): You can put this solution on YOUR website! t=D/r t=316/55 t=5.75 hrs, 5 hrs 45 min

Numbers_Word_Problems/237094: the plumber charges $75 to come to your house and $60 per hour labor. If steve , the plumber charges $435 how many hours did he work? set up equation and solve 1 solutions Answer 174421 by rfer(12657)   on 2009-11-09 22:18:11 (Show Source): You can put this solution on YOUR website! (435-75)/60=6 hrs

Numbers_Word_Problems/237164: . Metro Concerts can rent a truck for either $72 with unlimited mileage or $29 plus 52 cents per mile. For what mileages would the unlimited mileage plan save money? a. Write an inequality to describe the situation. (3 points) b. Solve the inequality. (3 points) 1 solutions Answer 174419 by rfer(12657)   on 2009-11-09 22:13:20 (Show Source): You can put this solution on YOUR website! 72<29+.52x 43<.52x 43/.52 81 81 miles is cheaper at the $29+.52/mi

Geometry_Word_Problems/237128: The length of the base of an isosceles triangle is one third the length of one of its legs. If the perimeter of the triangle is 56 inches, what is the length of the base. 1 solutions Answer 174416 by rfer(12657)   on 2009-11-09 22:08:59 (Show Source): You can put this solution on YOUR website! 2 1/3x=56 7/3x=56 x=56/(7/3) x=56*3/7 x=168/7 x=24 in legs base =8 in

Probability-and-statistics/237144: when an event is certain to occur, what is its probabiliti? 1 solutions Answer 174413 by rfer(12657)   on 2009-11-09 22:04:38 (Show Source): You can put this solution on YOUR website! 100%

Money_Word_Problems/237157: an invested 12000 i two accounts. one investment earned 7 % annual simple interest and the other investment earned 6.5% annual simple interest. the amount of interest for 1 year was 820. How much was invested at 6.5 % 1 solutions Answer 174411 by rfer(12657)   on 2009-11-09 22:03:31 (Show Source): You can put this solution on YOUR website! .07x+.065(12000-x)=820 .07x+780-.065x=820 .005x=40 x=$8000 at 7% $4000 at 6.5%

Polynomials-and-rational-expressions/237156: sovle the equation 3/x=7/5 1 solutions Answer 174410 by rfer(12657)   on 2009-11-09 22:00:11 (Show Source): You can put this solution on YOUR website! 3/x=7/5 3*5=7*x 7x=15 x=2 1/7

Trigonometry-basics/237149: Can you please tell me what is the value of cos 780 degrees? 1 solutions Answer 174409 by rfer(12657)   on 2009-11-09 21:58:51 (Show Source): You can put this solution on YOUR website! 0.5

Polynomials-and-rational-expressions/237151: what numbers can not be used for x in the rational expression 1/x 1 solutions Answer 174408 by rfer(12657)   on 2009-11-09 21:56:07 (Show Source): You can put this solution on YOUR website! "0"

Rectangles/237100: QUESTION ONE The perimeter of a rectangle parking lot is 146 meters. Find its dimensions if the length is 7 meters less than 4 times thw width QUESTION TWO The lenght of the second side of the triangle is 2 inches less tha the length of the first side. The length of the third side is 12 inches more than the length of the first side. The perimter of the triangle is 73 inches. Find the length of each side of the triangle. THESE ARE LET STATMENTS! 1 solutions Answer 174407 by rfer(12657)   on 2009-11-09 21:55:11 (Show Source): You can put this solution on YOUR website! x-2+x+x+12=73 3x+10=73 3x=63 x=21 degrees x-2=19 degrees x+12=33 degrees

Money_Word_Problems/237142: a doughnut shop has a fixed cost of $124 per day and a variable cost of $.12 per doughnut. Find the daily cost of producing x doughnuts? how many dougnuts can be produced for a total daily cost of $250? 1 solutions Answer 174406 by rfer(12657)   on 2009-11-09 21:49:44 (Show Source): You can put this solution on YOUR website! 250=124+.12x 126=.12x x=1050 doughnuts

Numbers_Word_Problems/237103: a cashmere sweater has a wholesale price of $400. the store marks it up increases by 25%. what does the store sell the sweater for? set up equation and solve. 1 solutions Answer 174405 by rfer(12657)   on 2009-11-09 21:47:11 (Show Source): You can put this solution on YOUR website! 400*1.25=$500

Geometry_proofs/237139: A bottled water company charges $8 per month for a water cooler and $5 per bottle b of water. Write an equation that represents the total cost C for monthly water service. 1 solutions Answer 174404 by rfer(12657)   on 2009-11-09 21:44:20 (Show Source): You can put this solution on YOUR website! C=8+5b

Geometry_Word_Problems/237113: A painter leans a 15-ft ladder against a house. The base of the ladder is 5 ft from the house. a)To the nearest tenth of a foot, how high on the house does the ladder reach? b) The ladder in part (a) reaches too high on the house. By how much should the painter move the ladder's base away from the house to lower to top by 1ft? 1 solutions Answer 174403 by rfer(12657)   on 2009-11-09 21:42:56 (Show Source): You can put this solution on YOUR website! a)=14.1 ft b)=7.3 ft

Equations/237137: 4a+8a=144 1 solutions Answer 174402 by rfer(12657)   on 2009-11-09 21:38:31 (Show Source): You can put this solution on YOUR website! 4a+8a=144 12a=144 a=12

Inequalities/237122: Solve the inequality: 5-x-2>3 1 solutions Answer 174401 by rfer(12657)   on 2009-11-09 21:37:55 (Show Source): You can put this solution on YOUR website! 5-x-2>3 3-x>3 -x>1 x<-1

Geometry_Word_Problems/237130: the width of an official volleyball court is half its length. The perimeter is 54 meters. find the dimensions of the court. 1 solutions Answer 174400 by rfer(12657)   on 2009-11-09 21:35:42 (Show Source): You can put this solution on YOUR website! P=2w+2L 54=2(.5L)+2L 54=L+2L 3L=54 L=18 m .5L=9 m

Geometry_Word_Problems/237124: the perimeter of a rectangle is 200 feet. the width is two-thirds as long as length. what are the dimensions of the rectangle 1 solutions Answer 174399 by rfer(12657)   on 2009-11-09 21:33:00 (Show Source): You can put this solution on YOUR website! P=2w+2L 200=2(2/3L)+2L 200=4/3L+2L 200=10/3L L=200/(10/3) L=200*3/10 L=600/10 L=60 ft 2/3L=40 ft

Inequalities/237127: Write an inequality: The sum of half a number and two-thirds of the number is less than 14 1 solutions Answer 174397 by rfer(12657)   on 2009-11-09 21:28:55 (Show Source): You can put this solution on YOUR website! 1/2x+2/3x<14

Travel_Word_Problems/237116: sorry gave wrong address before...a motorist drives 450 miles in 8 hours. on the journey he averages 60 mph before noon and 50 mph after. what were his departure and arrival times? i used formula d=rt, d=450. i know i don't add the 2 rates, but do i average the averages to solve for t (r=55) , 8.01 ...wrong! i also found the average travel time for the whole trip is 56.25 mph ...doesn't help. how do i solve for t? 450=60 t + 50 t??? thanx for reading 1 solutions Answer 174396 by rfer(12657)   on 2009-11-09 21:27:40 (Show Source): You can put this solution on YOUR website! total time is 8 hrs the ratio is 5/6 8:22 am 4:22 pm

Circles/237121: the radius is 11.7cm what is the circumference 1 solutions Answer 174392 by rfer(12657)   on 2009-11-09 21:16:31 (Show Source): You can put this solution on YOUR website! 11.7*2*3.14=73.476 cm

Pythagorean-theorem/237118: I was wondering if in the theorum of a2 + b2 = c2 if you can designate all the values as 1 so that the equation would read 1 squared + 1 squared = 1 squared? If you can not do this, I was wondering if you could explain to me why that is? Thank you! 1 solutions Answer 174390 by rfer(12657)   on 2009-11-09 21:14:55 (Show Source): You can put this solution on YOUR website! Pythagorean Theorum is used with right triangles. 1 over and 1 up, the distance from point to point will be more than 1. 1 sq + 1 sq =2, it's the sq rt of 2, which is 1.4142

Coordinate-system/237117: what is the x-intercept of the graph of the equation x-2y=6? 1 solutions Answer 174388 by rfer(12657)   on 2009-11-09 21:09:23 (Show Source): You can put this solution on YOUR website! x-2y=6 x int, y=0 x-2(0)=6 x=6 (6,0)

Functions/237049: (0,5),m=-2 write the equation in standard form of the line that passes through the given point and has a slope of M or that passes throught the two given points 1 solutions Answer 174364 by rfer(12657)   on 2009-11-09 19:01:02 (Show Source): You can put this solution on YOUR website! y+2x=5

Travel_Word_Problems/237028: At a rate of 50 miles per houer, a car travels at a rate of 600 mph. How far will the car travel at a rate of 40 mph if it is driven the same amount of time? 1 solutions Answer 174362 by rfer(12657)   on 2009-11-09 18:54:44 (Show Source): You can put this solution on YOUR website! 600/50=12 hr 12*40=480 miles

Sequences-and-series/237041: What is the sum of 3 6/7 + 1 1/2? 1 solutions Answer 174361 by rfer(12657)   on 2009-11-09 18:47:16 (Show Source): You can put this solution on YOUR website! 3 6/7+1 1/5 3 30/35+1 7/35 8 37/35 9 2/35

Coordinate-system/237042: what is the slope of a line that contains the points (-2,5) and (6,-3) 1 solutions Answer 174360 by rfer(12657)   on 2009-11-09 18:45:04 (Show Source): You can put this solution on YOUR website! slope m=-1