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Rational-functions/309528: Add the rational expression. + 1 solutions Answer 221394 by Fombitz(13828)   on 2010-05-28 22:18:58 (Show Source): You can put this solution on YOUR website! + Let's do some simplification first.

Rational-functions/309475: Sir/Madam: Here is the link of the question. http://img198.imageshack.us/img198/9893/maths3.jpg Only Question 16 is to be answered. Actually, the problem lies in 16(c). If you got the answer, please explain it to me. 1 solutions Answer 221331 by Fombitz(13828)   on 2010-05-28 16:17:14 (Show Source): You can put this solution on YOUR website! Find the inverse of Interchange x and y, and solve for y. This new y is the inverse function f^(-1)(x) that they're looking for.

Probability-and-statistics/309447: a card is drawn from a deck of cards numbered one through twenty. The card is NOT replaced and another card is drawn. Find the probability that a prime number is drawn and then a composite number. 1 solutions Answer 221328 by Fombitz(13828)   on 2010-05-28 16:14:41 (Show Source): You can put this solution on YOUR website! Prime numbers from 1 to 20 are 2, 3, 5, 7, 11, 13, 17, 19 The number 1 is neither prime nor composite (if your teacher doesn't feel that way then modify as necessary). That makes 8 numbers prime. 11 numbers composite. 1 special number (the number 1). 20 total. P(prime)=8/20=2/5 Without replacement the total number of cards drops to 19. P(composite)=11/19 P(prime, composite)=(2/5)(11/19)=22/95

Surface-area/309449: The volume of a cylindrical can is 500 cubed cm. the material used to make the top and bottom costs .o12 cent/squared cm, the material used for the sides costs .01 cent/ squared cm, and the seam joining the top and bottom to the sides costs .015 cent/cm. what size can would cost the least to produce? 1 solutions Answer 221325 by Fombitz(13828)   on 2010-05-28 16:07:15 (Show Source): You can put this solution on YOUR website! The can is a cylinder of radius R and length L. The total cost is the cost of the top and bottom plus the cost of the sidewall. The costs are based on total area. The top and bottom are both circles of radius R. The contribution to the total cost is, and width . Its contribution to the total cost is, The final contributor to cost is the seam which is length L. Its contribution is The total cost equation is then Using the volume equation you can get L as a function of R. Now substitute into the cost equation, Now you have total cost as the function of one variable. To find the minimum cost, take the derivative and set it equal to zero. I solved this numerically in EXCEL and got From that, then use the volume equation to find R.

Quadratic_Equations/309439: Can you factor 3x^2+25x-14 please? 1 solutions Answer 221310 by Fombitz(13828)   on 2010-05-28 14:32:35 (Show Source): You can put this solution on YOUR website! Can't be factored cleanly. Solve for the roots by either using the quadratic formula or completing the square.

Probability-and-statistics/309436: Two dice are rolled. Find the probability that both dice show the same number 1 solutions Answer 221307 by Fombitz(13828)   on 2010-05-28 14:12:24 (Show Source): You can put this solution on YOUR website! There are 36 possible outcomes rolling two dice. 6 of them are double 1,1 2,2 3,3 4,4 5,5 6,6 P(doubles)=6/36=1/6

logarithm/309431: Question: e^(x-1) - 5 = 5 What do I have to do differently in my calculations when there is a log e ? How do I solve this? (Also how would I do this on my calculator? It's a Ti-84 Plus) 1 solutions Answer 221306 by Fombitz(13828)   on 2010-05-28 14:04:42 (Show Source): You can put this solution on YOUR website!

Probability-and-statistics/309423: a number cube is rolled and a number card is drawn from the cards numbered 1-14.find the possible outcomes for the situation. 1 solutions Answer 221304 by Fombitz(13828)   on 2010-05-28 13:23:49 (Show Source): You can put this solution on YOUR website! (Cube Number,Card Number) (1,1)(1,2)(1,3)(1,4)(1,5)(1,6)(1,7)(1,8)(1,9)(1,10)(1,11)(1,12)(1,13)(1,14) (2,1)..... Repeat each row exactly with the same card number and vary the cube number from 2,3,..,6 to get all possible combinations. There are (6x14=) 84 of them.

Graphs/309304: 4y-12=6x 1 solutions Answer 221303 by Fombitz(13828)   on 2010-05-28 13:19:55 (Show Source): You can put this solution on YOUR website!

Probability-and-statistics/309422: In a bag there are 20 red marbles and 15 black ones. By no replacement, find the probability that randomly selecting four marbles, they are all red. 1 solutions Answer 221302 by Fombitz(13828)   on 2010-05-28 13:18:55 (Show Source): You can put this solution on YOUR website! 20 R, red 15 B, black 35 total to start P(R)=20/35=4/7 w/o replacement P(R)=19/34 w/o replacement P(R)=18/33=6/11 w/o replacement P(R)=17/32 Multiply the probabilities, P(R,R,R,R)=(4/7)(19/34)(6/11)(17/32) P(R,R,R,R)=(19*3)/(7*2*11*4) P(R,R,R,R)=57/616

Linear-equations/309348: Find the intercepts the graph 3x-6y=1 ** Could you please show me how you did this??** Thank you so much!!! 1 solutions Answer 221301 by Fombitz(13828)   on 2010-05-28 13:14:23 (Show Source): You can put this solution on YOUR website! To find the x-intercept, set y=0 and solve for x. (1/3,0) . . . To find the y-intercept, set x=0 and solve for y. (0,-1/6)

Permutations/309397: FIND THE CHANCE OF THROWING MORE THAN 15 IN ONE THROW WITH 3 DICE. 1 solutions Answer 221300 by Fombitz(13828)   on 2010-05-28 13:12:16 (Show Source): You can put this solution on YOUR website! Throwing 3 dice gives a possible 216 outcomes. Of those, 10 sum to greater than 15. 4 6 6 5 5 6 5 6 5 5 6 6 6 4 6 6 5 5 6 5 6 6 6 4 6 6 5 6 6 6 So the probability, P(Sum>15)=10/216=5/108

Linear-equations/309350: Solve using the elimination method: If a system has an infinite number of solutions, use set- builder notation to write the solution set. If a system has no solution sates this: 5x-3y=8 -5x+y=4 Please show me how you came up with the answer? Thank you!!! 1 solutions Answer 221299 by Fombitz(13828)   on 2010-05-28 13:06:34 (Show Source): You can put this solution on YOUR website! Add the two equations together to eliminate x. Solve for y, then go back and solve for x. Then use either equation to solve for x.

Equations/309356: The expression a^-2 b^3/a^4 ^-2 is equivalent to 1 solutions Answer 221298 by Fombitz(13828)   on 2010-05-28 13:03:56 (Show Source): You can put this solution on YOUR website!

real-numbers/309393: Is 13/2 an irrational number?? 1 solutions Answer 221296 by Fombitz(13828)   on 2010-05-28 13:01:33 (Show Source): You can put this solution on YOUR website! No, it's a rational number, a ratio of two integers. It's the ratio between 13 and 2.

expressions/309400: Translate to an algebraic expression. Use x and y for variables. 1 solutions Answer 221295 by Fombitz(13828)   on 2010-05-28 13:00:28 (Show Source): You can put this solution on YOUR website! More information needed. Please re-post.

Number-Line/309412: decide whether the pair of lines is parallel, perpendicular, or neither 4x + 5y = 8 4x + 5y = 3 1 solutions Answer 221294 by Fombitz(13828)   on 2010-05-28 12:59:25 (Show Source): You can put this solution on YOUR website! Parallel. Same relationship between x and y on the left hand side means the slopes are identical, hence the lines are parallel.

Linear_Algebra/309378: Graph each system of constraints. Find all vertices. Evaluate the objective function at each vertex to find the maximum or minimum value. 1)x<3 y<7 x>0,y>0 maximum for p=2x+3y 2) 2x+y<30 x+y<20 x>0, y>0 minimum for c=x+4y 3. Jerome burns 4 cal/min walking and 10 cal/min running. He walks between 10 and 20 min each day and runs between 30 and 45 min each days. He never spends more than an hour running and walking together. How much time should he spend on each activity to maximize the number of calories he burns? 1 solutions Answer 221278 by Fombitz(13828)   on 2010-05-28 11:10:14 (Show Source): You can put this solution on YOUR website! 1)P(X,Y)=2X+3Y P(0,0)=0+0=0 P(0,7)=0+3(7)=21 P(3,0)=2(3)+0=6 P(3,7)=2(3)+3(7)=27 The max occurs at (3,7). . . . 2)C(X,Y)=X+4Y C(0,0)=0+0=0 C(0,20)=0+4(20)=80 C(15,0)=15+0=15 C(10,10)=10+4(10)=50 The min occurs at (0,0). . . . Let C(X,Y) be the calories burned walking X minutes and running Y minutes. C(X,Y)=4X+10Y Constraints: 10<=X<=20, 30<=Y<=45. 1)C(X,Y)=4X+10Y C(10,30)=4(10)+10(30)= 340 C(10,45)=4(10)+10(45)=490 C(20,30)=4(10)+10(30)=380 C(20,45)=4(10)+10(45)=530 The max occurs at (10,45). 10 minutes walking, 45 minutes running.

Equations/309355: Write the quadratic equation given the sum of the roots equal 2 and the product of the roots equal 3/4 1 solutions Answer 221271 by Fombitz(13828)   on 2010-05-28 10:54:29 (Show Source): You can put this solution on YOUR website! For a quadratic equation, , the product of the roots equals the sum of the roots equals . . . . . where can take on any non-zero value.

Graphs/309374: Graph each system of constraints. Find all vertices. Evaluate the objective function at each vertex to find the maximum or minimum value. 1. x <= 3 y <= 7 x >= 0 y >= 0 2. 2x + y <= 30 x + y <= 20 x >= 0 y >= 0 1 solutions Answer 221269 by Fombitz(13828)   on 2010-05-28 10:47:31 (Show Source): You can put this solution on YOUR website! You have only provided the feasible regions for both problems with no objective functions. Please re-post.

Linear-equations/309373: Find the distance between the pair of points, round to the nearest tenth if neccessary,(-10,4) and (6,12). Thankyou 1 solutions Answer 221268 by Fombitz(13828)   on 2010-05-28 10:45:03 (Show Source): You can put this solution on YOUR website! Use the distance formula

Equations/309362: Simplify 5/12-sqrt2 1 solutions Answer 221267 by Fombitz(13828)   on 2010-05-28 10:41:20 (Show Source): You can put this solution on YOUR website!

absolute-value/309341: solve /x-10/=5 1 solutions Answer 221245 by Fombitz(13828)   on 2010-05-28 09:28:07 (Show Source): You can put this solution on YOUR website! Absolute value problems are really two problems in one. Positive solution: . . . Negative solution

Sequences-and-series/309331: fi8nd the sum of the arithmetic series.-4,+1+6+11+........+91 1 solutions Answer 221244 by Fombitz(13828)   on 2010-05-28 09:26:17 (Show Source): You can put this solution on YOUR website! The sum of an arithmetic series is, Solve for n using the final term. Then

Probability-and-statistics/309336: 3. Find the mean and standard deviation of the following probability distribution: x 1 2 3 P(x) 0.1 0.6 0.3 1 solutions Answer 221242 by Fombitz(13828)   on 2010-05-28 09:21:51 (Show Source): You can put this solution on YOUR website! Mean, . . . Standard Deviation,

Miscellaneous_Word_Problems/309329: we are interested in demensions of a certain square. a rectangle has length 5 units more than the side of the square and the width half the side of the square. if two areas are equal. What are the squares demensions( w x h) 1 solutions Answer 221241 by Fombitz(13828)   on 2010-05-28 09:15:22 (Show Source): You can put this solution on YOUR website! Square dimensions : s x s Rectangle dimensions : 5+s x s/2 The area of the square is, The area of the rectangle is, The areas are equal,

Probability-and-statistics/309338: 7. Find the value of z such that 25% of the distribution lies between it and the mean. 1 solutions Answer 221239 by Fombitz(13828)   on 2010-05-28 09:12:16 (Show Source): You can put this solution on YOUR website! The z-score for p=0.25 is z=-0.67449, using NORMSINV in EXCEL.

Linear-equations/309334: I need help the question its on this site http://www.wiziq.com/tutorial/71913-Math 1 solutions Answer 221235 by Fombitz(13828)   on 2010-05-28 08:58:06 (Show Source): You can put this solution on YOUR website! Which question? There are 30 of them.

Probability-and-statistics/309110: The table shows a simulation to predict how many cars will arrive at a car wash. Each event represents how many cars arrive during a ten-minute period. Use the six randomly generated numbers 63, 13, 87, 59, 27, and 2 to predict how many cars will arrive over a one-hour period. The table is here: http://i45.tinypic.com/218ub8.jpg 1 solutions Answer 221233 by Fombitz(13828)   on 2010-05-28 08:55:36 (Show Source): You can put this solution on YOUR website! Find the corresponding number of cars to each random number: 63-2 13-0 87-3 59-2 27-1 2-0 Sum them to find the number of cars in 1 hour period.

Linear_Equations_And_Systems_Word_Problems/309328: write the negation of the statement All horses have manes 1 solutions Answer 221230 by Fombitz(13828)   on 2010-05-28 08:30:26 (Show Source): You can put this solution on YOUR website! No horses have manes.

Inequalities/309297: How many times do you check your answer for an inequality? 1 solutions Answer 221229 by Fombitz(13828)   on 2010-05-28 08:28:38 (Show Source): You can put this solution on YOUR website! If it's a single inequality, like , then only once. If there are multiple inequalities, then more.