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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-axis 1 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^2b 1 solutions Answer 231854 by Fombitz(13828)   on 2010-07-20 09:31:59 (Show Source): You can put this solution on YOUR website!

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=0 1 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)=3 1 solutions Answer 231840 by Fombitz(13828)   on 2010-07-20 09:03:38 (Show Source): You can put this solution on YOUR website!

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 8/153 1 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 inches 1 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 x 1 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=3 1 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): You can put this solution on YOUR website!

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+24 1 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): You can put this solution on YOUR website!

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;8 1 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): You can put this solution on YOUR website!

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? thankyou 1 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^2 1 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.