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# Recent problems solved by 'rfer'

rfer answered: 12726 problems
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 Polynomials-and-rational-expressions/466841: Short Answer. Find the following product: -5z(5z^3+2z^2-9) I got -(25z^4+10z^3-45z) is this correct? 1 solutions Answer 320114 by rfer(12730)   on 2011-07-03 17:51:14 (Show Source): You can put this solution on YOUR website!-25z^4-10z^3+45z
 Expressions-with-variables/466840: Hello, I have a question on solving linear equations. What would be the solution to this problem? 0.92x + 0.98(12-x) = 0.96(12) Thank you1 solutions Answer 320112 by rfer(12730)   on 2011-07-03 17:44:10 (Show Source): You can put this solution on YOUR website!0.92x+11.76-0.98x=11.52 -0.06x=-0.24 x=-0.24/-0.06 x=4
 Expressions-with-variables/466838: Hello, What would be the correct solution to this problem on solving linear equations? 2/3k - (k - 1/2) = 1/6(k - 5) Thank you1 solutions Answer 320109 by rfer(12730)   on 2011-07-03 17:41:17 (Show Source): You can put this solution on YOUR website!2/3k-k+1/2=1/6k-5(1/6) 2/3k-k-1/6k=-5/6-1/2 4/6k-6/6k-1/6k=-5/6-3/6 -3/6k=-8/6 k=(-8/6)/(-3/6) k=-8/6*-6/3 k=48/18 k=2 2/3
 Expressions-with-variables/466836: Hello, I have a question on solving linear equations. Please adivse with a solution to this problem. 1/9(p + 18) + 1/3(2p + 3) = p + 3 I tried this several time but get the wrong answer. Thank you1 solutions Answer 320105 by rfer(12730)   on 2011-07-03 17:35:26 (Show Source): You can put this solution on YOUR website!1/9*p+1/9*18+1/3*2p+1/3*3=p+3 1/9(p)+2+2/3(p)+1=p+3 1/9(p)+2/3(p)-p=3-3 p=0
 test/466810: To buy both a new car and a new house, Tina sought two loans totalling \$332,888. The simple interest rate on the first loan was 8.9%, while the simple interest rate on the second loan was 6.0%. At the end of the first year, Tina paid a combined interest payment of \$20,230.51. What were the amounts of the two loans? 1 solutions Answer 320101 by rfer(12730)   on 2011-07-03 17:23:41 (Show Source): You can put this solution on YOUR website!0.089x+0.06(332888-x)=20230.51 0.089x+19973.28-0.06x=20230.51 0.029x=257.23 x=257.23/0.029 x=8870 at 8.9% 332888-8870=324018 at 6%
 Linear-equations/466829: Find the x and y intercepts for the equation show all work. then graph the equation y= -2x - 61 solutions Answer 320097 by rfer(12730)   on 2011-07-03 17:11:25 (Show Source): You can put this solution on YOUR website!y=-2*0-6 y=-6 (0,-6) -------------- 0=-2x-6 2x=-6 x=-3 (-3,0)
 Volume/466793: Simplify each expression. You may use the properties to help. When you type your answer, do not leave spaces between numbers and symbols. (4a)(5b)(6c) 1 solutions Answer 320075 by rfer(12730)   on 2011-07-03 14:59:35 (Show Source): You can put this solution on YOUR website!=120ABC
 Finance/466641: I need help with this question please.. Warwick wins \$2800 and decides to start a savings fund to buy a car.He researches two banks to find the best investment deal.He finds the following information: Trust Me Credit Union 7.4% pa.(nominal)compounded monthly No Frills Bank 7.5% (nominal) compounded half yearly a.) By calculating the effective interest rate(algebraically),decide which bank gives a better deal. b.) If he decided to save with the No Frills Bank,approximately how long would it take for his money to double?(use the rule of 70) c.) Check your answer to part b) using a more exact method. 1 solutions Answer 320074 by rfer(12730)   on 2011-07-03 14:58:11 (Show Source): You can put this solution on YOUR website!A=2800(1+0.074/12)^12 A=2800(1.00617)^12 A=2800*1.0766 A=3014.48 ------------------- A=2800(1+0.075/2)^2 A=2800(1.0375)^2 A=2800*1.0764 A=1313.92 -------------- 9.33 yrs ------------ You do last part
 Permutations/466653: a teacher sets 5 objective type questions out of which 4 have to be answered. find out the total number of ways in which they can be answered if first 2 questions have 4 choices and last 3 have 3 choices. 1 solutions Answer 320046 by rfer(12730)   on 2011-07-03 13:41:50 (Show Source): You can put this solution on YOUR website!2*4+3*3=17
 Pythagorean-theorem/466711: show whether the points lie in a straight line 1. (0,-1), (1,0), (3,2) ? 1 solutions Answer 320045 by rfer(12730)   on 2011-07-03 13:39:43 (Show Source): You can put this solution on YOUR website!They are a straight line. Just graph them.
 Percentage-and-ratio-word-problems/466738: A businessman spends P4,500 for labor to produce 6,750 units of his products. If he will produce 20,250 units, how much will he spend for labor?1 solutions Answer 320044 by rfer(12730)   on 2011-07-03 13:38:02 (Show Source): You can put this solution on YOUR website!20250/6750=3 4500*3=\$13,500
 Evaluation_Word_Problems/466773: Solve using the substitution method. Show your work. If the system has no solution or an infinite number of solutions, state this. Please show all your work. -7x + 7y = -7 x + 9y = 61 1 solutions Answer 320043 by rfer(12730)   on 2011-07-03 13:35:41 (Show Source): You can put this solution on YOUR website!x=61-9y -7x+7y=-7 -7*(61-9y)+7y=-7 -427+63y+7y=-7 70y=420 y=6 -------------- -7x+7*6=-7 -7x+42=-7 -7x=-49 x=7 ------------- 7+9*6=61
 Evaluation_Word_Problems/466743: Please help me on this one. I get confused with Word Problems!!! Please help me :) Thanks so much!!! J.Bond and E.Blofeld are driving speedboats in opposite directions after a failed attempt by the latter to blow up the world with a nuclear bomb. Mr.Bonds boat is going 25 MPH faster than Mr.Blofelds. After 3 hours they are 500 miles apart. How fast was each of them going?1 solutions Answer 320040 by rfer(12730)   on 2011-07-03 13:30:44 (Show Source): You can put this solution on YOUR website!x+x+25=500/3 2x+25=167 2x=142 x=71 mph x+25=96 mph
 Percentage-and-ratio-word-problems/466727: Successive discounts of 10%, 20%, 30% equal to a discount of ?1 solutions Answer 320019 by rfer(12730)   on 2011-07-03 12:09:01 (Show Source): You can put this solution on YOUR website!\$10*.9=9*.8=7.2*.7=\$5.04 5.04/10=0.504=50.4% I like to work from real numbers.
 Equations/466751: What is X? 6x+13=-32-9x -112-7x=8x+23 5-10x=32-31x 105-2x=16x+23 4x+41=9x-141 solutions Answer 320016 by rfer(12730)   on 2011-07-03 12:04:20 (Show Source): You can put this solution on YOUR website!15x=-45 x=-3
 Linear_Equations_And_Systems_Word_Problems/466675: two cyclists start at the same point and travel in opposite directions. one cyclist travels8km/h faster than the other. if the two cyclists are 270km apart after 5 hours what is the rate of each cyclist?1 solutions Answer 319954 by rfer(12730)   on 2011-07-02 22:06:33 (Show Source): You can put this solution on YOUR website!x+x+8=270/5 2x+8=54 2x=54-8 2x=46 x=23 kph x+8=31 kph
 Evaluation_Word_Problems/466612: You have 10 cups of sugar. Your cookie recipe calls for 1¼ of sugar for one batch. What is the greatest number of batches of cookies you could make with the sugar that you have? 1 solutions Answer 319935 by rfer(12730)   on 2011-07-02 20:38:35 (Show Source): You can put this solution on YOUR website!10/1.25=8 batches
 Volume/466650: In an 8 inch square cake pan and a 9 inch ssquare cake pan, what is the difference in volume each pan will hold? Assume each pan is 1.5 inches high. Show step by step work. Include correct units with your solution.1 solutions Answer 319933 by rfer(12730)   on 2011-07-02 20:36:28 (Show Source): You can put this solution on YOUR website!8*8*1.5=96 9*9*1.5=121.5 25.5 difference
 Probability-and-statistics/466618: You have administered a standardized test of manual dexterity to two groups of 10 semi skilled workers. One of these two groups of workers will be employed by you to work in a warehouse with many fragile items. The higher the manual dexterity of a worker the less likelihood that worker will break significant inventory. Because of a unique contract you must hire all 10 employees from one of the two groups and none of the employees from the other. Group A Scores 63, 79, 64. 83, 87,81, 89, 75, 91, 78 Group B Scores 98, 89, 26, 65, 100, 93, 59, 60, 100, 100. You must decide which group to choose. Choose at least two measures of central tendency and at least one measure of dispersion for each group and use those to make your choice.1 solutions Answer 319932 by rfer(12730)   on 2011-07-02 20:34:30 (Show Source): You can put this solution on YOUR website!a) mean=79 median=80 b) mean=79 median=91
 Volume/466648: I have a drilled well 6inches in diameter by 355 feet deep if the well and casing is full to top ,how many gallons is there in that well1 solutions Answer 319929 by rfer(12730)   on 2011-07-02 20:24:50 (Show Source): You can put this solution on YOUR website!V=pir^2L V=3.14*0.25^2*355 V=69.69 cu ft 69.69*7.45=520 gallons
 Volume/466652: In an 8 in. square cake pan and a 10 in. square cake pan, what is the difference in volume each pan holds? Assume each pan is 2.5 in. high. Show step by step work1 solutions Answer 319927 by rfer(12730)   on 2011-07-02 20:15:58 (Show Source): You can put this solution on YOUR website!8*8*2.5=160 10*10*2.5=250 90 cu in difference
 Mixture_Word_Problems/466639: If you invested \$7,363, and you receive \$370 in interest, what annual interest rate did you receive on your investment? If necessary, round your answer to the nearest hundredth. 1 solutions Answer 319903 by rfer(12730)   on 2011-07-02 17:42:53 (Show Source): You can put this solution on YOUR website!I=Prt I/(Pt)=r 370/7363=0.05=5%
 Linear-equations/466619: solve using the elimination method this is what I did -3x+4y=1 (1) -6x+6y=-3 muli both sides of problem 1 by -2 6x-8y=-2 -6x+6=-3 =-2y=-5 y=5/2 sub 5/2 for y inequation 1 -3x+4(5/2)=1 -3x+10=1 x=-3 y=5/2,x-31 solutions Answer 319902 by rfer(12730)   on 2011-07-02 17:37:06 (Show Source): You can put this solution on YOUR website!looks good
 Exponents/466627: Hello! I have a hard time with fractions. Here is my problem, and I wish to know if I worked it out correctly. (3/4x + 1/2)^2 = (3/4x + 1/2) (3/4x + 1/2) = 3/4x * 3/4x = 9/16x^2 --> 3/4x * 1/2 (((2/4 * 3/4x)) = 6/16x = 1/2 * 1/2 = 1/4 = 9/16x^2 + 6/16x + 6/16x + 1/4 = 9/16x^2 + 12/16x + 1/4 I want to know if I worked this problem out correctly. 1 solutions Answer 319901 by rfer(12730)   on 2011-07-02 17:34:39 (Show Source): You can put this solution on YOUR website!9/16^2+3/4x+1/4
 Pythagorean-theorem/466631: The legs of a right triangle are 15 inches and 6 inches. Waht is the length of the hypotenuse?1 solutions Answer 319900 by rfer(12730)   on 2011-07-02 17:33:33 (Show Source): You can put this solution on YOUR website!15^2+6^2=c^2 225+36=261 sq rt 261=16.2 in
 Distributive-associative-commutative-properties/466632: Hello! I have a hard time with fractions. Here is my problem, and I wish to know if I worked it out correctly. (3/4x + 1/2)^2 = (3/4x + 1/2) (3/4x + 1/2) = 3/4x * 3/4x = 9/16x^2 --> 3/4x * 1/2 (((2/4 * 3/4x)) = 6/16x = 1/2 * 1/2 = 1/4 = 9/16x^2 + 6/16x + 6/16x + 1/4 = 9/16x^2 + 12/16x + 1/4 I want to know if I worked this problem out correctly. 1 solutions Answer 319899 by rfer(12730)   on 2011-07-02 17:31:57 (Show Source): You can put this solution on YOUR website!looks good except you need to reduce the middle value to 3/4x. Isn't it fun to try and keep track of all this stuff? Bob
 Percentage-and-ratio-word-problems/466637: Including 8% sales tax, a bed-and-breakfast inn charges \$172.80 per night. Find the inn's nightly cost before the tax is added. #2 A repair bill on a sailboat came to \$1603, including \$532 for parts and the remainder for labor. If the cost of labor is \$63 per hour, how many hours of labor did it take to repair the sailboat?1 solutions Answer 319898 by rfer(12730)   on 2011-07-02 17:25:52 (Show Source): You can put this solution on YOUR website!A) 172.80/1.08=\$160 B) 1603-532=1071 1071/63=17 hrs
 Distributive-associative-commutative-properties/466634: Hello! I am working on my Foiling, and I wish to know if I worked it out correctly. (7x + 4y)^2 = (7x + 4y)(7x + 4y) = 49x^2 + 28xy + 28xy + 16y^2 = 49x^2 + 56xy + 16y^2 Thanks 1 solutions Answer 319897 by rfer(12730)   on 2011-07-02 17:23:10 (Show Source): You can put this solution on YOUR website!looks good to me. Good luck. Bob
 Percentage-and-ratio-word-problems/466636: This years salary,\$42,074 is a 9% increase over last year's salary. What was last years salary?1 solutions Answer 319896 by rfer(12730)   on 2011-07-02 17:21:08 (Show Source): You can put this solution on YOUR website!42074/1.09=38,600
 Rectangles/466524: a rectangular field is twice as long as its width. if its area is 14450 square meters , find its sides1 solutions Answer 319878 by rfer(12730)   on 2011-07-02 14:09:39 (Show Source): You can put this solution on YOUR website!x*2x=14450 2x^2=14450 x^2=14450/2 x^2=7225 x=85 2x=170
 Rectangles/466526: the length of a rectangular field is five times its breadth. if its area is 37845 square meters , find its sides?1 solutions Answer 319877 by rfer(12730)   on 2011-07-02 14:05:58 (Show Source): You can put this solution on YOUR website!x*5x=37845 5x^2=37845 x^2=37845/5 x^2=7569 x=87 5x=435