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Probability-and-statistics/117457: A bag contains 10 blue, 6 red, and 4 green rubber balls. If you select a ball at random from the bag, what is the probability of not choosing a green ball? A. 1/5 B. 4/5 C. 5/6 D. 9/10 Why can you eliminate choice D in this question? 1 solutions Answer 85459 by Fombitz(13828)   on 2007-12-18 15:16:21 (Show Source): You can put this solution on YOUR website! The total number of balls available is 10+6+4=20 balls. The probability of choosing a blue ball is 10/20. The probability of choosing a red ball is 6/20. The probability of choosing a green ball is 4/20. P(green or not green) = 1, since the ball I choose must be either green or not green. P(green) + P(not green) = P(green or not green) 4/20 + P(not green) = 1 P(not green) = 16/20 = 4/5 The answer is B. You can eliminate D because none of the probability can sum to 18 out of 20(9/10). The only possible choices are 16/20, 14/20, or 10/20. You can also eliminate C because it's not possible to sum to repeating fraction from the possible probabilities (0.5,0.3,0.2).

Linear-systems/117448: http://i147.photobucket.com/albums/r317/fizzero/graph.jpg ^that is the link to the graph. what is the slope and verticle intercept for the line? m=? and y-intercept= what is the equation of the line? using the least square method what is the correlation coefficient? r= ?? 1 solutions Answer 85457 by Fombitz(13828)   on 2007-12-18 14:56:59 (Show Source): You can put this solution on YOUR website! From your graph, you have 9 (x,y) data pairs. First, make a table with the x,y data points. Add 5 columns to your table. 1. 2. 3. 4. 5. 6. 7. where is the average of the x values and is the vaverage of the y values. Calculate the values for i=1 to 9. Sum columns 5,6,7. You are solving for the regression equation where or and From this we see that is the slope of the regression line. is the y-intercept of the regression line. is the equation of the regression line. To calculate the , you need to calculate two more quanitities, and where or and or and N is the number of data points, 9. The coefficient, , is then calculated from EXCEL is the perfect program to do this kind of work. Good luck. Post another question if you get stuck.

Graphs/117451: We have graphed a boundary line for the linear inequality. Determine the correct half-plane and complete the graph. y>3. Would the inequality then become y=3? I have the graph with the shaded area completed, but would the boundary line remain slashed or should it be a solid line? Thank You, Barb Neely 1 solutions Answer 85452 by Fombitz(13828)   on 2007-12-18 13:58:00 (Show Source): You can put this solution on YOUR website! The boundary line defines the region where . If the inequality is , then the line is also included and made solid. If the inequality is , like you mentioned, then the line is not included, only shows the boundary and should be dashed or dotted (non-solid).

Polynomials-and-rational-expressions/117452: factor completely: x^2 -6wy +3xy - 2wx The w is throwing me off somehow. Please Help! Thank you 1 solutions Answer 85451 by Fombitz(13828)   on 2007-12-18 13:53:13 (Show Source): You can put this solution on YOUR website! Try to ignore it. Group the terms (w and non-w).

Quadratic-relations-and-conic-sections/117445: Sketch graph of the following conic sections. 2 2 (x-3) +(y-1) =36 1 solutions Answer 85450 by Fombitz(13828)   on 2007-12-18 13:47:48 (Show Source): You can put this solution on YOUR website! That conic section is a circle centered at (3,1) with a radius of 6. It's graphed here with some missing sections at the edges. The general formula for a circle centered at (h,k) wih a radius R is,

Numbers_Word_Problems/117441: Let A be the set of all composites less than 10, and B be the set of positive even integers less than 10. How many different sums of the form a + b are possible if a is in A and b is in B? 1 solutions Answer 85449 by Fombitz(13828)   on 2007-12-18 13:33:42 (Show Source): You can put this solution on YOUR website! A=(4,6,8,9) B=(2,4,6,8) C is the set of all unique sums of members of A and B. C=(6,8,10,11,12,13,14,15,16,17) C has 10 members in it.

Linear-equations/117394: A student has scores of 87, 81, and 88 on the first 3 of 4 test. If the student wants to an average of exactly 87, what score must she earn on the fourth test 1 solutions Answer 85448 by Fombitz(13828)   on 2007-12-18 13:26:23 (Show Source): You can put this solution on YOUR website! Let T be the test score on the fourth test. The student needs to get exactly a 92 to get exactly an 87 average.

Linear-systems/117401: Find two consecutive integers such that the sum of 2 times the frist integer and 7 times second integer is 88 1 solutions Answer 85423 by Fombitz(13828)   on 2007-12-18 09:04:32 (Show Source): You can put this solution on YOUR website! First integer : N Second integer (consecutive): N+1 The integers are 9 and 10. Check your answer. True statement. Good answer.

Systems-of-equations/117425: graph each system one solution no solution many solution 4x-2y=-6 2x-y=-3 1 solutions Answer 85422 by Fombitz(13828)   on 2007-12-18 09:00:18 (Show Source): You can put this solution on YOUR website! 1.4x-2y=-6 2.2x-y=-3 First graph equation 1. When x=0, -2y=-6, y=3. When y=0, 4x=-6, x=-3/2 Next, equation 2. 2.2x-y=-3 When x=0, -y=-3, y=3. When y=0, 2x=-3, x=-3/2. As you see the x and y intercepts are the same for equations 1 and 2. Equations 1 and 2 are the same equation. If you multiply equation 2 by (2), you get equation 1. They have infinitely many solutions.

Rational-functions/117324: can you help me with this problem? A parabola is congruent to y=x^2 and has x-intercepts 1 and 5. determine the coordinates of the vertex 1 solutions Answer 85360 by Fombitz(13828)   on 2007-12-17 16:14:19 (Show Source): You can put this solution on YOUR website! A parabola is symmetric about the vertex. If you take the average of the x intercepts you will find the x coordinate of the parabola. The general equation, congruent to , is then, Find by using either point, The vertex is (3,-4).

Linear-equations/117320: Hello I really need some help with this math problem it deal with Coordinate Geometry: Linear Equations in Two Variables. What is the equation of the line that contains the points with (x,y) coordinates (-3,7) and (5,-1) ? I don't have clue how to set this type of problem up, please help. thanks 1 solutions Answer 85350 by Fombitz(13828)   on 2007-12-17 15:13:56 (Show Source): You can put this solution on YOUR website! You need to use the point-slope method of a line. First calculate the slope, m. It's the change in y divided by the change in x. Your points are given as (x,y) pairs. Your first point is (-3,7). Your second point is (5,-1). That means that the change in y is equal to the change in x (all except the negative). The slope is negative which means as x gets larger, y gets smaller. You can generate points on your line using this. Add 1 to x. Subtract 1 from y. (-3,7) (-2,6) (-1,5) (0,4) (1,3) (2,2) (3,1) (4,0) (5,-1) Next, use the point slope form of the line. where m is the slope you just calculated. (,) are either of the two points you already know. Use the first point (-3,7) We would have gotten the same answer if we used the second point. Use the second point (5,-1)

Quadratic_Equations/117315: Can you help me with this problem? A parabola has vertex (8,3) and one x-intercept. Determine the coordinates of the other x-intercept. 1 solutions Answer 85345 by Fombitz(13828)   on 2007-12-17 14:55:04 (Show Source): You can put this solution on YOUR website! The x distance from the vertex to the first x intercept is the same as the distance from the vertex to the second x intercept. A vertical line through the vertex is a line of symmetry. For example, has a vertex at (1,-1) The first x intercept is x=0, 1 unit away from the vertex. The second x intercept is x=2, also 1 unit away from the vertex.

Proportions/117310: Please explain how to do this whith ratios.; my problem is this:attendence at the concert was 480. the ratio from adults to kids was 5/3. how many kids were there? 1 solutions Answer 85336 by Fombitz(13828)   on 2007-12-17 14:15:17 (Show Source): You can put this solution on YOUR website! When you say the ratio was 5:3 adults to kids, that means that out of 8 (5+3), 5 were adults and 3 were students. You can then set up a ratio. If 3 out of 8 are kids, then the total number of kids, X, to the total attendance is in a ratio. There were 180 kids (and 300 adults) in attendance.

Radicals/117272: fraction problem numerator sqrt5-2x denominator 3 =1 1 solutions Answer 85305 by Fombitz(13828)   on 2007-12-17 08:31:40 (Show Source): You can put this solution on YOUR website! From your explanation, I think this is what you mean, Multiply both sides by (3). Square both sides. Subtract (5) from boths sides. Divide both sides by (-2). Always check your answer. True statement. Good answer.

Polynomials-and-rational-expressions/116844: Perform the indicated divisions. x^2-2x-35/x+5 1 solutions Answer 84955 by Fombitz(13828)   on 2007-12-14 15:04:12 (Show Source): You can put this solution on YOUR website!

Equations/116828: (6p-w)/(w-4) - (4c+p)/(w-4) 1 solutions Answer 84953 by Fombitz(13828)   on 2007-12-14 14:55:50 (Show Source): You can put this solution on YOUR website! Since it both expressions have the same denominator, you can subtract numerators.

Rational-functions/116815: If f(x) = 2x + 3 and g(x) = (x - 3)/2, what is the value of f[g(-5)]? If f(x) = 5x - 7, what is f -1(x)? 1 solutions Answer 84950 by Fombitz(13828)   on 2007-12-14 14:46:50 (Show Source): You can put this solution on YOUR website! If f(x) = 5x - 7, what is f -1(x)? To find the inverse, we have to find a function g such that,

Exponential-and-logarithmic-functions/116807: factor completely 3x^2-2x-8 1 solutions Answer 84929 by Fombitz(13828)   on 2007-12-14 11:00:24 (Show Source): You can put this solution on YOUR website!

Human-and-algebraic-language/116805: How many 6 in. x 6 in. tiles would be needed to cover a floor that is 96 square feet? 1 solutions Answer 84923 by Fombitz(13828)   on 2007-12-14 10:01:36 (Show Source): You can put this solution on YOUR website! Each tile takes up 6x6=36 square inches. The entire floor is 96 square feet. In terms of square inches, it would be 96 sq.ft x 12 in/ft x 12 in/ft=13824 square inches. If we divide the total area by the are of one tile, we can find how many tiles are needed. 144 tiles are needed to cover the floor.

Matrices-and-determiminant/116768: Determine whether the matrix has an inverse. If an inverse exists, find it. -1 - 1 2 3 1 solutions Answer 84921 by Fombitz(13828)   on 2007-12-14 09:55:54 (Show Source): You can put this solution on YOUR website! A matrix has an inverse if its determinant is not equal to zero. For a 2x2 matrix, The determinant is In this case the determinant is The inverse of a 2x2 matrix is given by, In this case

Radicals/116793: X+1=radical 17-4x 1 solutions Answer 84920 by Fombitz(13828)   on 2007-12-14 09:37:00 (Show Source): You can put this solution on YOUR website! and Check your answers Remember the square root can be +7 or -7 True statement. True statement. Good answers

Human-and-algebraic-language/116800: solve 2x^2-11x-6=0 1 solutions Answer 84919 by Fombitz(13828)   on 2007-12-14 09:31:04 (Show Source): You can put this solution on YOUR website!

Average/116757: This question is from textbook algebra how many grams of sugar must be added to 60 grams of a solution that is 32% sugar to obtain a solution that is 50% sugar 1 solutions Answer 84914 by Fombitz(13828)   on 2007-12-14 09:25:01 (Show Source): You can put this solution on YOUR website! The 32% solution has 0.32*(60)=19.2 grams of sugar. A 50% solution would have 0.50*(60)=30 grams of sugar. You would have to add the difference. 30-19.2 = 10.8 grams.

Coordinate-system/116769: How far apart are the y-intercepts of the line with the equation y=2x + 3 and the line goes through the point (4,2) and has a slope of -1? 1 solutions Answer 84913 by Fombitz(13828)   on 2007-12-14 09:21:28 (Show Source): You can put this solution on YOUR website! The first line, , has a y-intercept of y=3. The second line, using the point-slope form, is, The second line's y-intercept is y=6. The difference in y-interecept, the distance, is 3.

Functions/116798: State the domain of the following m(x)= 5/x^2+9 1 solutions Answer 84911 by Fombitz(13828)   on 2007-12-14 09:15:23 (Show Source): You can put this solution on YOUR website! The domain of the function is all values of x where the function exists. For an equation like this, the only problem area is when the denominator equals zero. Since x is squared plus a positive value, that will never happen. Therefore the range is all x in (,).

test/116623: The demand for corn obeys the equation p(x) = 320 - 25x, where p is the price per bushel (in dollars) and x is the number of bushels produced, in millions. Express the production amount x as a function of the price p. 1 solutions Answer 84809 by Fombitz(13828)   on 2007-12-13 16:29:16 (Show Source): You can put this solution on YOUR website! Subtract 320 from both sides of the equation. Divide both sides of the equation by (-25).

Rational-functions/116634: True or False? The expression x(squared)-3x-10 / x-5 is exactly the same as the expression x+ 2 Justify your answer 1 solutions Answer 84807 by Fombitz(13828)   on 2007-12-13 16:18:43 (Show Source): You can put this solution on YOUR website! True. You can factor into .

Miscellaneous_Word_Problems/116629: This question is from textbook Algebra Structure and Method Evaluate if r=1/2 (r-3)(r)(r+3) ------------- (r-2)(r+2) If anyone can answer this question I would appreciate it very much. Please and Thank You 1 solutions Answer 84805 by Fombitz(13828)   on 2007-12-13 16:15:57 (Show Source): You can put this solution on YOUR website!

Equations/116579: Factor Completely 1. 3x^-2x-8 2. 24x^+10x-4 (include the check of your answer using multiplication)(suppose to be factoring the polynomials) 3.2(x+y)^(2)+(x+y)-3 1 solutions Answer 84804 by Fombitz(13828)   on 2007-12-13 16:09:38 (Show Source): You can put this solution on YOUR website! 1. You can look at all combinations of factors of 8 for a and b to see which ones can actually solve both equations. Since you have 2 equations and two unknowns, you can create another quadratic equation to solve and find the answer. We'll do this on number 1 to show how. and , 2. 3. First use a substitution to transform the equation to ,

logarithm/116572: Suppose that the function P=12 +50 ln x represents the percentage of inbound e-mail in the US that is considered spam, where x is the number of years after 2001. Use this model to approximate the year that the percent of spam will reach 90% provided that law enforcement regarding spammers does not change. 1 solutions Answer 84745 by Fombitz(13828)   on 2007-12-13 09:27:04 (Show Source): You can put this solution on YOUR website! That's approximately 4 years 9 months From 2001, the year would be 2005.

Miscellaneous_Word_Problems/116518: a)The Graph of a linear equation ___________ has an x-intercept. 1. Never 2. Sometimes 3. Always b) If y varies directly with x, the constant of variation k is ________negative. 1. Never 2. Sometimes 3. Always c) Complete the Statement: "The difference between undefined slope and zero slope is___". d) Complete the Statement: "The slope of the line tells you____". 1 solutions Answer 84742 by Fombitz(13828)   on 2007-12-13 09:06:11 (Show Source): You can put this solution on YOUR website! a. Sometimes. y=5 has no x intercept. y=x+1 has an x intercept of x=-1. b. Sometimes. y=5x has a positive constant. y=-5x has a negative constant. c. A zero slope has no rise and is a horizontal line while an undefined slope has no run and is a vertical line. d. the rise over the run or what angle it makes with the y axis. Small slope values are shallow and have small angles with the y axis while large slope values are steep and make large angles with the y axis.