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 Probability-and-statistics/323894: A random sample of 20 health maintenance organizations (HMOs) was selected. For each HMO, the co-payment (in dollars) for a doctor's office visit was recorded. The results are as follows: 11,8,9,12,8,6,9,6,6,7,9,5,11,8,5,10,7,7,5,12 Under the assumption that co-payment amounts are normally distributed, find a 90% confidence interval for the mean co-payment amount in dollars. Then complete the table below. What is the lower limit of the confidence interval? What is the upper limit of the confidence interval?1 solutions Answer 231861 by Fombitz(13828)   on 2010-07-20 09:48:49 (Show Source): You can put this solution on YOUR website! Sample size is less than 30 (). Sample standard deviation is known (not the population ). Use t distribution instead of z distribution to construct interval. Degrees of freedom () equals . For and 90%, the critical t value is (,) (,)
 Graphs/323867: Write the function whose graph is the graph of y=x^4, but is: a. shifted up 14 units b. reflected about the x-axis1 solutions Answer 231859 by Fombitz(13828)   on 2010-07-20 09:39:31 (Show Source): You can put this solution on YOUR website!a) . . . . . . b) . . . . . .
 Quadratic-relations-and-conic-sections/323978: what is the y-coordinate of the vertwx of the parabola that is given by the equation below? y=1.5(x-2)^2+7 1 solutions Answer 231858 by Fombitz(13828)   on 2010-07-20 09:37:08 (Show Source): You can put this solution on YOUR website!Compare to the vertex form, where the vertex is (,). Comparing, (,)=(,) The y-coordinate is .
 Linear-equations/323857: Find the equation of the line passing through the points (-1,2) and (3,-4). Give the equation in slope-intercept form and express non-integer numbers in fractional form.1 solutions Answer 231857 by Fombitz(13828)   on 2010-07-20 09:35:59 (Show Source): You can put this solution on YOUR website!Find the slope first, Then use the slope-intercept form of a line, Use either point to solve for b, . . . . . . . .
 Problems-with-consecutive-odd-even-integers/323944: Factor completely. If a polynomial is prime, state this. a^4b^3 + 2a^3b^2 − 15a^2b1 solutions Answer 231854 by Fombitz(13828)   on 2010-07-20 09:31:59 (Show Source):
 Sequences-and-series/323970: Determine whether f(x)= -5x^2 - 10x + 6 has a maximum of minimum value and find that value.1 solutions Answer 231852 by Fombitz(13828)   on 2010-07-20 09:29:27 (Show Source): You can put this solution on YOUR website!Convert to vertex form, by completing the square. The vertex occurs at (-1,11). The coefficient for the term is negative and the parabola opens downward, the value at the vertex is the maximum. . . .
 Linear-equations/323974: Find the y-intercept for the graph of the following equation. 18x + 12y = 72 1 solutions Answer 231850 by Fombitz(13828)   on 2010-07-20 09:24:25 (Show Source): You can put this solution on YOUR website!To find the y-intercept, set and solve for . . . . (0,6)
 Equations/323975: Which quadratic equation has roots 7 and -2/3? a) 2x^2 - 11x - 21=0 b) 3x^2 - 19x - 14=0 c) 3x^2 + 23x + 14=0 d) 2x^2 + 11x - 21=01 solutions Answer 231849 by Fombitz(13828)   on 2010-07-20 09:23:36 (Show Source): You can put this solution on YOUR website! where is any non-zero constant, Let , b) is the correct answer.
 Numbers_Word_Problems/323968: if the average of 5 consecutive integers is 12. what is the sum of the least and greatest of the 5 integers ? A 24 B 14 C 12 D 11 E 10 1 solutions Answer 231846 by Fombitz(13828)   on 2010-07-20 09:18:26 (Show Source): You can put this solution on YOUR website! , the least integer , the greatest integer (some of the other integers disagree)
 Equations/323967: How do you write a prediction equation for data points shown in a scatter plot?1 solutions Answer 231842 by Fombitz(13828)   on 2010-07-20 09:12:47 (Show Source): You can put this solution on YOUR website!Same as you would for a line, although the symbols are different, . . . where and are the means of the input data, are the sum of the squares of the x deviations, are the products of the x and y square deviation terms.
 Probability-and-statistics/323963: 1)A card is drawn at random from an ordinary pack of 52 playing cards.Find the probability of finding a)an ace b)a six or a heart c)neither a nine or a spade 2)Two cards are drawn at random from an ordinary pack of 52 playing cards.Find the probability(P) that one is a diamond and the other is a heart please give me the answers by tomorrow as it very urgent......1 solutions Answer 231841 by Fombitz(13828)   on 2010-07-20 09:08:27 (Show Source): You can put this solution on YOUR website!1a) 4 aces in 52 cards, P(ace)=4/52=1/13 1b) P(6)=4/52, P(heart)=13/52, P(6 of hearts)=1/52 P(6 or heart)=P(6)+P(heart)-P(6 of hearts)=4/52+13/52-1/52=16/52=4/13 1c) P(9)=4/52, P(spade)=13/52, P(9 of spades)=1/52 P(9 or spade)=4/13 P(not 9 or spade)=1-4/13=9/13 . . . 2) I assume you mean they are drawn without replacement. P(diamond)=4/52=1/13 P(heart)=4/51 P(diamond, heart)=(1/13)(4/51)=4/663
 logarithm/323962: 2log2(5-x)=31 solutions Answer 231840 by Fombitz(13828)   on 2010-07-20 09:03:38 (Show Source):
 Probability-and-statistics/323960: A bag of marbles has 5 green, 2 yellow, 8 red, and 3 purple marbles. What is the probability of picking a purple marble, not replacing it, and then picking another purple marble? My Choices Are: 28/153 1/51 20/153 8/1531 solutions Answer 231836 by Fombitz(13828)   on 2010-07-20 08:50:03 (Show Source): You can put this solution on YOUR website!5 Green 2 Yellow 8 Red 3 Purple 18 total . . . P(1st Purple)= w/o replacement, P(2nd Purple)= P(both Purple)=
 Surface-area/323949: what is the total surface of a cube is 78 square inches1 solutions Answer 231835 by Fombitz(13828)   on 2010-07-20 08:45:20 (Show Source): You can put this solution on YOUR website!I think you're asking for the measure of the side of a cube with surface area of 78 sq. in. A cube is made up of 6 faces, each a square of side . inches.
 Graphs/323958: Please help me solve this problem: 9<2y+11<17 The solution x1 solutions Answer 231834 by Fombitz(13828)   on 2010-07-20 08:42:50 (Show Source): You can put this solution on YOUR website! <--- Subtract 11 from all terms, <--- Divide all terms by 2.
 Matrices-and-determiminant/323866: 3a-b-3c=14,2a-b+3c=5,a+2b-4c=31 solutions Answer 231833 by Fombitz(13828)   on 2010-07-20 08:40:19 (Show Source): You can put this solution on YOUR website![A]= [x]= [b]= . . . [A][x]=[b] [x]=[A]inv[b] . . . det[A]=-32 [A]inv=
 logarithm/323943: Solve for: 25(2x-1)= 5(5+1)1 solutions Answer 231831 by Fombitz(13828)   on 2010-07-20 08:35:18 (Show Source):
 Trigonometry-basics/323911: Can you please help me to solve this problem. The question reads; Find all solutions of the multiple-angle equation cos4x(cosx-1)=0 Thanks,1 solutions Answer 231830 by Fombitz(13828)   on 2010-07-20 08:34:02 (Show Source): You can put this solution on YOUR website!Solutions are for (,) Two paths to solutions: and and . . . and
 Exponential-and-logarithmic-functions/323886: 3X^6+241 solutions Answer 231829 by Fombitz(13828)   on 2010-07-20 08:29:20 (Show Source): You can put this solution on YOUR website!What's the question? . . .
 Rational-functions/323209: (k-3)/(k-2)-(k-4)/(k-1)=(3k+2)/(k^2-3k+2)1 solutions Answer 231828 by Fombitz(13828)   on 2010-07-20 08:27:58 (Show Source): You can put this solution on YOUR website! Use the common denominator Multiply both sides by
 logarithm/323946: Solve for x: log(x-3) - log(x-2) = log(x+1)1 solutions Answer 231827 by Fombitz(13828)   on 2010-07-20 08:18:10 (Show Source):
 Systems-of-equations/323820: The perimeter of a rectangle is 20 inches and its area is 24 square inches. What are its dimensions?1 solutions Answer 231799 by Fombitz(13828)   on 2010-07-20 00:42:52 (Show Source): You can put this solution on YOUR website!The area of a rectangle is, 1. The perimeter of a rectangle is, 2. From eq. 2, Substitute into eq. 1, Two solutions: Then from eq. 2, . . . The rectangle is 4 inches by 6 inches.
 Average/323815: is the given number a solution of the equation? c=2c-4;81 solutions Answer 231798 by Fombitz(13828)   on 2010-07-20 00:39:40 (Show Source): You can put this solution on YOUR website! Let False, so is not a solution of the equation.
 Linear-equations/323856: Need help with the following problem: Compute the slope of the line containing the points (-8,1) and (1/3,3).1 solutions Answer 231797 by Fombitz(13828)   on 2010-07-20 00:37:58 (Show Source):
 Systems-of-equations/323821: 1.) y = 6x^2 - 5x y = 2x + 3 2.) y = x^2 - 3x -3 y = -x^2 + 5x + 7 1 solutions Answer 231796 by Fombitz(13828)   on 2010-07-20 00:36:05 (Show Source): You can put this solution on YOUR website!#1: 1. 2. Since they both equal y, set them equal to each other. Two solutions: The use either equation to solve for y, (3/2,6) . . . (-1/3,7/3) . . . . . . #2: Same approach 1. 2. Two solutions: (5,7) . . . (-1,1) . . .
 Linear-equations/323859: Find the equation of the line parallel to the line y = 2x - 3 which contains the point (1,3). Express answer in slope-intercept form.1 solutions Answer 231795 by Fombitz(13828)   on 2010-07-20 00:24:59 (Show Source): You can put this solution on YOUR website!Parallel lines have identical slopes. THe slope of the first line is Use the slope-intercept form of a line, and use the point(1,3) to solve for b. . . .
 Functions/323823: Find the minimum and maximum values of z=2x+3y if possible, for the following set of constraints x+y≤9 -x+y≤5 2x-y≤14 Find minimum value & maximum value. Please help! :) 1 solutions Answer 231794 by Fombitz(13828)   on 2010-07-20 00:22:48 (Show Source): You can put this solution on YOUR website!First find the feasible region using the constraints. Find the intersection points. (2,7) . . . (-5/3,32/3) . . . (-9,-4) . . . . . . The min and max of the function will occur at one of the vertices: . . . (2,7): (-5/3,32/3): (-9,-4): . . . The min value of z of -30 occurs at (-9,-4). The max value of z of 86/3 occurs at (-5/3,32/3).
 Quadratic-relations-and-conic-sections/323853: What is the graph of 11x-x^2-4y^2 = 2y-16? thankyou1 solutions Answer 231793 by Fombitz(13828)   on 2010-07-20 00:11:57 (Show Source): You can put this solution on YOUR website!Complete the square in x and y. It's an ellipse.
 Linear-equations/323858: Find the equation of the line with slope m = 1 which contains the point (5,0). Give answer in slope-intercept form.1 solutions Answer 231791 by Fombitz(13828)   on 2010-07-20 00:04:12 (Show Source): You can put this solution on YOUR website!Use the point-slope form of a line,
 Exponential-and-logarithmic-functions/323846: 4x^2 + 12xy + 9y^2 - z^21 solutions Answer 231789 by Fombitz(13828)   on 2010-07-20 00:03:15 (Show Source): You can put this solution on YOUR website!What's the question?
 Functions/323833: Find the x and y intercepts (if any) of the rational function f(x) = (x^2 + 3x + 2)/(x + 1)1 solutions Answer 231788 by Fombitz(13828)   on 2010-07-20 00:01:32 (Show Source): You can put this solution on YOUR website! When , , (0,2) is the y-intercept. When , , (-2,0) is the x-intercept.