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rfer answered: 12656 problems
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Percentage-and-ratio-word-problems/252760: Thirty pounds of a salt-water solution contains fifteen percent salt. How much salt is in the water? 1 solutions Answer 184842 by rfer(12660)   on 2009-12-30 23:00:35 (Show Source): You can put this solution on YOUR website! 30(.15)=4.5 pounds

Linear-systems/252764: S= 2B+PH solve for H 1 solutions Answer 184841 by rfer(12660)   on 2009-12-30 22:58:48 (Show Source): You can put this solution on YOUR website! s=2b+ph s-2b=ph (s-2b)/p=h

Finance/252738: Find the present value of the following amount. $50,000 in 5 years and 6 months at 12% compounded quarterly 1 solutions Answer 184810 by rfer(12660)   on 2009-12-30 18:51:37 (Show Source): You can put this solution on YOUR website! p=a/(1+r/n)^nt p=50000/1+.12/4)^4*5 p=50000/(1.03)^20 p=50000/1.81 p=$27,624.31

Graphs/252573: Two video rental clubs offer two different rental fee plans: Club A charges $12 for membership and $2 for each rented video. Club B has a $3 membership fee and charges $3 for each rented video. The graph represents the total cost of renting videos from Club A. (a) An equation of the line representing the total cost of renting videos from Club B is y = x + . (b) For what number of video rentals is it less expensive to belong to Club A? videos 1 solutions Answer 184555 by rfer(12660)   on 2009-12-29 13:12:28 (Show Source): You can put this solution on YOUR website! B) 12+2x=3+3x 9=x

Expressions-with-variables/252572: 14x+(8x+4)=180 1 solutions Answer 184554 by rfer(12660)   on 2009-12-29 13:10:07 (Show Source): You can put this solution on YOUR website! 14x+(8x+4)=180 14x+8x+4=180 22x=176 x=8

Money_Word_Problems/252507: What simple interest rate will Susan need to secure to make $2,500 in interest on a $10,000 principle over 5 years? 1 solutions Answer 184472 by rfer(12660)   on 2009-12-28 21:49:47 (Show Source): You can put this solution on YOUR website! i=prt 2500=10000r5 2500=50000r 2500/50000=r r=.05=5%

Human-and-algebraic-language/252505: on a recent vacation, your uncle spent a total of $680 on airfare,hotel,and a rental car. the airfare cost twice as much as hotel, and the rental car was one-third as much as the hotel. use a linear system and Cramer's rule to find how much your uncle paid for each service 1 solutions Answer 184471 by rfer(12660)   on 2009-12-28 21:25:38 (Show Source): You can put this solution on YOUR website! af=2x=408 h=x=208 rc=1/3x=68 2x+x+1/3x=680 3 1/3x=680 x=680/3 1/3 x=680*3/10 x=2040/10 x=204 2x=408 1/3x=68

Human-and-algebraic-language/252503: Tom,Bob and Joe are brothers. their combined ages are 47. Joe was born 3 years before Bob and 4 years after Tom. How old is each brother? 1 solutions Answer 184470 by rfer(12660)   on 2009-12-28 21:20:42 (Show Source): You can put this solution on YOUR website! tom x=14 bob x+4=18 joe x+1=15 x+x+4+x+1=47 3x+5=47 3x=42 x=14 x+4=18 x+1=15

Rectangles/252341: A farmer has 2400 feet of fencing and wants to fence off a rectangular field that borders a straight river. Find the dimensions of the fence to maximize the area enclosed by the fence. 1 solutions Answer 184204 by rfer(12660)   on 2009-12-26 22:46:27 (Show Source): You can put this solution on YOUR website!

test/252333: Please help me solve this problem: Manuel plans to install a fence around the perimeter of his yard. His yard is shaped like a square and has an area of 40,000 square feet. The company that he hires charges $2.50 per foot for the fencing and $50.00 for the installation fee. What will be the cost of the fence in dollars? - I'm really stuck on this problem... PLEASE HELP!! thank you :) 1 solutions Answer 184187 by rfer(12660)   on 2009-12-26 18:50:17 (Show Source): You can put this solution on YOUR website! sq rt of 40000 is 200 so you have 800 ft of perimeter 800*2.50+50=$2050.00

Numbers_Word_Problems/252332: Hi, I needed help with math, and came across this site. Can you help me with this problem? the sum of two numbers is 47 and their difference is 15, what is the larger number? 1 solutions Answer 184186 by rfer(12660)   on 2009-12-26 18:40:51 (Show Source): You can put this solution on YOUR website! x+x+15=47 2x=32 x=16 x+15=31

Functions/252273: Suppose you invest $1600 at an annual interest rate of 4.6% compounded continuously. How much will you have in the account after 4 years? 1 solutions Answer 184115 by rfer(12660)   on 2009-12-25 22:28:03 (Show Source): You can put this solution on YOUR website! A=Pe^rt A=1600*2.7183^.046*4 A=1600*1.2 A=$1923.23

Numbers_Word_Problems/252234: There are three times as many chocolate cupcakes as vanilla ones. If 1/4 of the chocolate cupcakes have sprinkles, what fractional part are chocolate with sprinkles? 1 solutions Answer 184068 by rfer(12660)   on 2009-12-25 12:51:18 (Show Source): You can put this solution on YOUR website! 3/4*1/4=3/16

Average/252042: How many hours will it take to travel 100 miles at 70 mph? 1 solutions Answer 183786 by rfer(12660)   on 2009-12-22 12:10:47 (Show Source): You can put this solution on YOUR website! t=D/r t=100/70 t=1.43 hrs=1 hr 26 min

percentage/252032: Mrs.Jones paid $55.73 over regular price for some clothes because of financing them at 19% for 8 months. How much was the regular price of the clothes? 1 solutions Answer 183780 by rfer(12660)   on 2009-12-22 11:36:11 (Show Source): You can put this solution on YOUR website! 55.73/0.19=$293.32 price

Money_Word_Problems/251920: a $14,500.00, 11% loan is dated May 17 and is due to be repaid on August 17. Assuming ordinary time, what is the ordinary interst on the loan? 1 solutions Answer 183701 by rfer(12660)   on 2009-12-21 19:53:03 (Show Source): You can put this solution on YOUR website! A=P(1+r/n)^t A=14500(1.0275)^.25 A=14500(1.0068) A=14598.60 interest = $98.60

Inequalities/251960: Weather - a news station guarantees the weather forecast will be within 3degrees F of the actual temperature, or the station will make a donation to a particular charity. If the station forecasts the temperature to be 78 degrees F, at what actual temperatures will the station begin to make a charity donation? 1 solutions Answer 183700 by rfer(12660)   on 2009-12-21 19:48:32 (Show Source): You can put this solution on YOUR website! 75 to 81 degrees

Money_Word_Problems/251921: based on exact time, calculate the ordinary interst on a 15 1/4%, $24,000.00 loan dated March 25 and maturing on July 25. 1 solutions Answer 183699 by rfer(12660)   on 2009-12-21 19:42:26 (Show Source): You can put this solution on YOUR website! A=P(1+r/n)^t A=24000(1.05)^.33 A=24000(1.016231) A=24389.55 Interest = $389.55

Money_Word_Problems/251922: Shea wholesalers received an order costing $18,500.00. The terms of payment were 3/15, N/45. The owner did not have sufficient cash to pay the invoice within the discount period. is it to their advantage to borrow the money for 30 days at 11%? if so how much money would they save? (assume a 360 day year) 1 solutions Answer 183697 by rfer(12660)   on 2009-12-21 19:37:59 (Show Source): You can put this solution on YOUR website! No, they can pay net in 45 days at no additional cost.

Proportions/251956: If Liz sang at a wedding for 20minutes and got paid $25, how much would she get paid for singing for 40minutes? write a proportion and then answer the question. how do you do this? 1 solutions Answer 183696 by rfer(12660)   on 2009-12-21 19:36:12 (Show Source): You can put this solution on YOUR website! 20/25=40/x 20x=1000 x=$50

Points-lines-and-rays/251957: If the points (3,2) and (x,-5) lie on a line whose slope is (-7/2), then x equals --i graphed it to see if i could do it and got x=1, but i got the answer wrong, please help. 1 solutions Answer 183694 by rfer(12660)   on 2009-12-21 19:33:43 (Show Source): You can put this solution on YOUR website! (5,-5)

Percentage-and-ratio-word-problems/251872: My favorite store was having a 15% off everything sale. The jeans I wanted were originally $49.99, but they were already marked down to $35.99 before the 15% discount. When I bought the jeans, what percent discount off the original price did I pay? (Round to the nearest tenth of a percent.) 1 solutions Answer 183561 by rfer(12660)   on 2009-12-21 11:15:25 (Show Source): You can put this solution on YOUR website! 35.99*.85=30.59 49.99-30.59=19.40 19.40/49.99=.388=38.8%

Volume/251810: How much volume does a square container that is 7 feet on a side have? 1 solutions Answer 183506 by rfer(12660)   on 2009-12-20 21:50:27 (Show Source): You can put this solution on YOUR website! V=7^3 V=343 cu ft

Surface-area/251616: The circumference of a circle is 18 pi. inches. Determine the area of the circle. 1 solutions Answer 183299 by rfer(12660)   on 2009-12-19 20:59:35 (Show Source): You can put this solution on YOUR website! 18/3.14=5.7 5.7/2=2.86 A=pir^2 A=3.14*2.86^2 A=25.68 sq in

Linear-equations/251597: Find the slope and the y-intercept for the following equation of a line: 5x + 10 y = 20 Slope = y-intercept = 1 solutions Answer 183289 by rfer(12660)   on 2009-12-19 19:54:53 (Show Source): You can put this solution on YOUR website! y int is when x=0 5(0)+10y=20 y=2 (0,2) --------------- 5x+10y=20 10y=5x+20 y=.5x+2 slope = .5

Expressions-with-variables/251608: Okay I have a problem I don't understand this problem...... Ben bought 8 notbooks for 24.50 some of the notebooks were 2.50 each and the other were 3.25 each if x represents the number of least expensive notebooks,write an equation that can be used to find the number of the least exspensive notebook purchased. 1 solutions Answer 183288 by rfer(12660)   on 2009-12-19 19:50:21 (Show Source): You can put this solution on YOUR website! 2.5x+3.25(8-x)=24.5 2.5x+26-3.25x=24.5 -.75x=-1.5 x=2 at $2.50 8-x=6 at $3.25

Percentage-and-ratio-word-problems/251498: Mr. Jones was offered a radio by one firm at $80. less discounts of 20% and 10%; another firm offered him the same radio at $80. less 30%. Which is the better offer and by how much? a) same price b) 1st, $1.60. c) 1st, $.80 d) 2nd, $1.60 e ) none of these 1 solutions Answer 183200 by rfer(12660)   on 2009-12-19 13:20:55 (Show Source): You can put this solution on YOUR website! 80*.8*.9=57.60 80*.7=56.00 answer D

Unit_Conversion_Word_Problems/251261: i have a one-story house that is 32-ft wide adn 48-ft long. I plan to build an addition 12-ft by 16-ft. That will the total area of the house be? 1 solutions Answer 183101 by rfer(12660)   on 2009-12-18 19:59:43 (Show Source): You can put this solution on YOUR website! 32*48+12*16= 1536+192=1728 Sq ft

Linear-equations/251421: I need to find the intercepts then use them to graph the equation 3y-9=3x 1 solutions Answer 183098 by rfer(12660)   on 2009-12-18 19:50:03 (Show Source): You can put this solution on YOUR website! x int is when y=0 y int is when x=0 3y-9=3 ----------- 3y-3x=9 3(0)-3x=9 x=-3 (-3,0) ---------- 3y-3(0)=9 y=3 (0,3)

Unit_Conversion_Word_Problems/250813: Jim has 3/4 of a yard of string which he wishes to divide into pieces yard long. How many pieces will he have? ( Sorry but i have no idea what type of problem this is) Thank You Very Much 1 solutions Answer 182664 by rfer(12660)   on 2009-12-16 21:41:26 (Show Source): You can put this solution on YOUR website! need more info?

Money_Word_Problems/250843: 80% of what number is 60. please explain in steps if you can 1 solutions Answer 182663 by rfer(12660)   on 2009-12-16 21:37:22 (Show Source): You can put this solution on YOUR website! 60/0.8=75