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# Recent problems solved by 'rfer'

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 logarithm/527623: I need help with money and compound interest for example principal \$8500 rate 7% compounding quartley for 5 years I am not sure how to set up and solve sets, also I am gettin confused with investments like finding the accumulated value of an investment for instance investment of \$2000 at 8% compounded semi annually for 9 years 1 solutions Answer 348986 by rfer(12644)   on 2011-11-07 16:15:21 (Show Source): You can put this solution on YOUR website!A=P(1+r/4)^nt A=8500(1+0.07/4)^20 A=8500(1.0175)^20 A=8500(1.4148) A=\$12,025.80 ----------------- same thing only divide rate by 2. A=2000(1+0.08/2)^18 A=2000(1.04)^18 A=2000(2.0258) A=\$4,051.60
 Travel_Word_Problems/527117: if one car leaves as 11:45 and travels at 30 miles per hour and anothere car leaves at 12:00 and travels at 45 miles per hour what time will they meet1 solutions Answer 348798 by rfer(12644)   on 2011-11-06 18:49:24 (Show Source): You can put this solution on YOUR website!30/4=7.5 mi lead 45-30=15 mph overtake speed 7.5/15=0.5 hrs 12:00+00:30=12:30 meet time
 Graphs/527119: Consider the demand equation below, where x represents the quantity demanded in units of a thousand and p is the unit price in dollars. p = -x2 + 11 (a) Determine the quantity demanded when the unit price is set at p = 7. units1 solutions Answer 348797 by rfer(12644)   on 2011-11-06 18:46:27 (Show Source): You can put this solution on YOUR website!7=-x^2+11 7-11=-x^2 -4=-x^2 x=2
 Equations/527047: i need help with this question: the question is: .... The cost of renting a DVD at a certain store is described by the function f(x)=4x+3 in which f(x) is the cost and x is the time in days. If Lupe has \$12 to spend, what is the maximum number of days that she can rent a single DVD if tax is not considered?1 solutions Answer 348794 by rfer(12644)   on 2011-11-06 18:43:53 (Show Source): You can put this solution on YOUR website!12=4x+3 12-3=4x 9=4x x=9/4 x=2 1/4 days
 Money_Word_Problems/527112: How much money must be invested at 12% simple interest to earn \$770 in 5 months?1 solutions Answer 348790 by rfer(12644)   on 2011-11-06 18:39:23 (Show Source): You can put this solution on YOUR website!I=Prt I/(rt)=P 770/(0.12/12*5)=P 770/0.05=P P=\$15,400
 Equations/527054: .solve the problem,show all wrk. the area of a triangle with base b and height h is given by the formula a= 1/2 bh find the area of a triangle with base 3 meters and height 10 meters 1 solutions Answer 348788 by rfer(12644)   on 2011-11-06 18:35:59 (Show Source): You can put this solution on YOUR website!a=1/2*3*10 a=15 sq meters
 Numbers_Word_Problems/527055: find a number such that 20 less than twice the number is 501 solutions Answer 348787 by rfer(12644)   on 2011-11-06 18:33:58 (Show Source): You can put this solution on YOUR website!2x-20=50 2x=50+20 2x=70 x=70/2 x=35
 Graphs/527100: What is the slope of the line that goes through the given points? (0,3) and (-9,1)1 solutions Answer 348786 by rfer(12644)   on 2011-11-06 18:30:31 (Show Source): You can put this solution on YOUR website!m=(1-3)/(-9-0) m=-2/-9 m=2/9
 test/527108: -5x - (7x+2)1 solutions Answer 348785 by rfer(12644)   on 2011-11-06 18:28:28 (Show Source): You can put this solution on YOUR website!=-12x-2
 Graphs/527110: Find the slope of each line from the given equation. y= -12x + 5 1 solutions Answer 348784 by rfer(12644)   on 2011-11-06 18:27:16 (Show Source): You can put this solution on YOUR website!y=mx+b slope m=-12
 Money_Word_Problems/527102: Use the formula for future value with simple interest to find the missing quantity. Round to the nearest tenth of a percent. A = \$5,750, P, = \$5,000, r = ?, t = 2 years1 solutions Answer 348783 by rfer(12644)   on 2011-11-06 18:25:06 (Show Source): You can put this solution on YOUR website!I=Prt I/Pt=r (5750-5000)/5000*2=r 750/10000=r r=0.075=7.5%
 Equations/527077: Please help me solve for A: 2A/3 = 8 + 4A1 solutions Answer 348780 by rfer(12644)   on 2011-11-06 18:19:38 (Show Source): You can put this solution on YOUR website!2a=(8+4a)(3) 2a=24+12a -10a=24 a=24/-10 a=-2 2/5
 Inequalities/526731: 2x+5y=8 6x+y=10 Can you help me solve this question1 solutions Answer 348664 by rfer(12644)   on 2011-11-05 23:22:00 (Show Source): You can put this solution on YOUR website!y=-6x+10 2x+5y=8 2x+5(-6x+10)=8 2x-30x+50=8 -28x=-42 x=1.5 -------------- 2*1.5+5y=8 3+5y=8 5y=5 y=1 ------------- 6*1.5+1=10 9+1=10
 percentage/526615: A meteorologist was accurate 90% of the time, reporting accurately for 45 days. How many days of weather did he report 1 solutions Answer 348643 by rfer(12644)   on 2011-11-05 20:18:10 (Show Source): You can put this solution on YOUR website!45/0.9=50 days
 Geometry_Word_Problems/526602: The volume of a cube is 64 ft. How many feet are on each side?1 solutions Answer 348595 by rfer(12644)   on 2011-11-05 18:16:37 (Show Source): You can put this solution on YOUR website!cu rt 64=4 ft
 percentage/526608: what is the original price of a pair of shoes if the sale price is 24\$ after a 20% disscount1 solutions Answer 348594 by rfer(12644)   on 2011-11-05 18:15:09 (Show Source): You can put this solution on YOUR website!24/0.8=\$30
 Expressions-with-variables/526619: Find the height of a cylinder with volume 2500pi feet and radius 10 feet1 solutions Answer 348593 by rfer(12644)   on 2011-11-05 18:12:08 (Show Source): You can put this solution on YOUR website!2500=3.14*10^2h h=2500/3.14*10^2 h=2500/314 h=7.96 ft
 Money_Word_Problems/526634: FRANCES LEFT A 22% TIP ON A MEAL. INCLUDING THE TIP, ITS COST WAS \$23.18. WHAT WAS THE COST OF THE MEAL BEFORE TIP? 1 solutions Answer 348592 by rfer(12644)   on 2011-11-05 18:09:26 (Show Source): You can put this solution on YOUR website!23.18/1.22=\$19.00
 Money_Word_Problems/526638: find selling price and cost if markup is 60% and gross profit is \$5.401 solutions Answer 348590 by rfer(12644)   on 2011-11-05 18:07:14 (Show Source): You can put this solution on YOUR website!5.40/0.6=\$9.00 cost 9.00+5.40=\$14.40 selling price
 Miscellaneous_Word_Problems/526639: Please help me on this question that makes no sense to me! Lisa delivers papers before school. She has a choice of being paid \$15 per week plus \$0.20 per subscription or \$25.00 per week plus \$0.10 per subscription. For what number of subscriptions does she make the same amount of money either pay schedule?1 solutions Answer 348589 by rfer(12644)   on 2011-11-05 18:04:38 (Show Source): You can put this solution on YOUR website!make the two choices equal to each other and solve. 15+0.20x=25+0.10x 0.20x-0.10x=25-15 0.10x=10 x=10/0.10 x=100 papers ------------- 15+0.20*100=35 25+0.10*100=35
 percentage/525992: 126 is 15% of what number? 31 is what percent of 248?1 solutions Answer 348281 by rfer(12644)   on 2011-11-03 20:59:38 (Show Source): You can put this solution on YOUR website!126/0.15=840 31/248=0.125=12.5%
 Systems-of-equations/525952: What is -5d+3(2d-7) simplified as?1 solutions Answer 348280 by rfer(12644)   on 2011-11-03 20:57:55 (Show Source): You can put this solution on YOUR website!-5d+6d-21 =d-21
 Geometry_Word_Problems/525360: what will it cost to to carpet a rectangular floor measuring 15 feet by 21 feet if the carpet costs 20.97 per square yard 1 solutions Answer 348069 by rfer(12644)   on 2011-11-02 20:38:03 (Show Source): You can put this solution on YOUR website!15*21=315 315/9=35 sq yds 35*20.97=\$733.95
 Money_Word_Problems/525362: 18,700 is 22% of the total goal. what is the total goal1 solutions Answer 348065 by rfer(12644)   on 2011-11-02 20:35:40 (Show Source): You can put this solution on YOUR website!18700/0.22=85,000
 Percentage-and-ratio-word-problems/525328: Ivan's gas tank is 1/2 full. After he buys 9 gallons of gas, it is 4/5 full. How many gallons can Ivan's tank hold? 1 solutions Answer 348062 by rfer(12644)   on 2011-11-02 20:34:35 (Show Source): You can put this solution on YOUR website!9/(1.5/5)=x 9*5/1.5=45/1.5 45/1.5=30 gal
 Geometry_Word_Problems/524479: In a scale drawing of a playground, the total lenght is 5 cm. The actual length is 45 feet. If the actual width of the playground is 60 feet what is its width on the drawing?1 solutions Answer 347760 by rfer(12644)   on 2011-11-01 16:38:01 (Show Source): You can put this solution on YOUR website!5/45=x/60 45x=300 x=300/45 x=6.7 cm
 Numeric_Fractions/524489: x + 10 5/8 = 16 1/41 solutions Answer 347758 by rfer(12644)   on 2011-11-01 16:35:41 (Show Source): You can put this solution on YOUR website!x=16 1/4-10 5/8 x=16 2/8-10 5/8 x=15 10/8-10 5/8 x=5 5/8
 Travel_Word_Problems/524481: if your going 85 mph how long will it take to travel 454 miles1 solutions Answer 347757 by rfer(12644)   on 2011-11-01 16:33:22 (Show Source): You can put this solution on YOUR website!454/85=5.34 hrs=5 hrs 20 minutes
 expressions/524485: How do you write 3.15x10 to the 4th power in standard form?1 solutions Answer 347754 by rfer(12644)   on 2011-11-01 16:31:38 (Show Source): You can put this solution on YOUR website!=31,500
 Exponential-and-logarithmic-functions/524112: 4-2.7 1 solutions Answer 347645 by rfer(12644)   on 2011-10-31 23:02:35 (Show Source): You can put this solution on YOUR website!=1.3
 test/524113: C=2 pie r,r solve for the indicated varible1 solutions Answer 347644 by rfer(12644)   on 2011-10-31 23:01:06 (Show Source): You can put this solution on YOUR website!r=C/(2pi)