• How do I calculate population standard deviation?

    Best answer: Step 1) Find the mean of the data points. Step 2) For every data point, subtract the mean from it Step 3) Square all results Step 4) Find the mean of the squares Step 5) Get the square root of the previous result
    Best answer: Step 1) Find the mean of the data points. Step 2) For every data point, subtract the mean from it Step 3) Square all results Step 4) Find the mean of the squares Step 5) Get the square root of the previous result
    1 answer · Mathematics · 2 weeks ago
  • Amazon sells "Chessmaster - Xbox".?

    Best answer: I can't speak for any backward compatibility, but that's a title designed for the original xbox (I call xbox prime so not to be confused with xbox one)
    Best answer: I can't speak for any backward compatibility, but that's a title designed for the original xbox (I call xbox prime so not to be confused with xbox one)
    2 answers · Xbox · 5 days ago
  • An open box with a rectangular base is to be constructed from a rectangular piece of cardboard 18 in wide and 22 in long by...?

    Best answer: Starting with a piece of cardboard that is 18" by 22", we have a starting length and width. If we cut out x" by x" squares from the corners, the length and widths each gets reduced by 2x (since there is a left and right side and a top and bottom side), so the new lengths and widths become: (18 - 2x) and (22 -... show more
    Best answer: Starting with a piece of cardboard that is 18" by 22", we have a starting length and width. If we cut out x" by x" squares from the corners, the length and widths each gets reduced by 2x (since there is a left and right side and a top and bottom side), so the new lengths and widths become: (18 - 2x) and (22 - 2x) with the height of the box being x The volume in terms of x is then: V(x) = lwh V(x) = (18 - 2x)(22 - 2x)x Simplify and put into standard form: V(x) = (396 - 36x - 44x + 4x²)x V(x) = (396 - 80x + 4x²)x V(x) = (4x² - 80x + 396)x V(x) = 4x³ - 80x² + 396x That's your function for volume in terms of x. For the domain of x, it cannot be zero otherwise you don't have a box. it can't be half of the smallest dimension since you will no longer have length. so the domain is: 0 < x < 9 So you can graph the function in this domain using whatever method you know of. To find the maximum volume, we can solve for the zero of the first derivative and throw out any value of x that is outside of this domain: V(x) = 4x³ - 80x² + 396x V'(x) = 12x² - 160x + 396 0 = 12x² - 160x + 396 Divide both sides by 2: 0 = 6x² - 80x + 198 Using quadratic equation: x = [ -b ± √(b² - 4ac)] / (2a) x = [ -(-80) ± √((-80)² - 4(6)(198))] / (2 * 6) x = [ 80 ± √(6400 - 4752)] / 12 x = [ 80 ± √(1648)] / 12 x = [ 80 ± √(16 * 103)] / 12 x = [ 80 ± 4√(103)] / 12 factor out a 4 and cancel out: x = [ 20 ± √(103)] / 3 Using 10.15 as an approximation for √103, we get: x = (20 + 10.15) / 3 and (20 - 10.15) / 3 x = 30.15 / 3 and 9.85 / 3 x = 10.05 and 3.283 We said that x had to be less than 9, so we can throw out the one answer, leaving this as the only value: x = (20 - √103) / 3 inches
    5 answers · Mathematics · 4 days ago
  • Can you explain this division? 613 divided by 71?

    Best answer: You eventually will when you find out that there are 0 71's in 6 and 0 71's in 61. So the next step is to see how many 71's in 613. If you can see it without having to use the zero placeholders, go ahead. Just note that if you end up with a remainder larger than your divisor, you missed a step.
    Best answer: You eventually will when you find out that there are 0 71's in 6 and 0 71's in 61. So the next step is to see how many 71's in 613. If you can see it without having to use the zero placeholders, go ahead. Just note that if you end up with a remainder larger than your divisor, you missed a step.
    4 answers · Mathematics · 4 months ago
  • What's the growth factor here?

    Best answer: I think your first row's Growth/Decay rate as a % is wrong. If the factor is 2.47, it's an increase of 147% (basically, subtract 1, then multiply by 100. This pattern is followed in the second row, 3.43 compared to 243%, is to subtract 3.43 by 1 and then multiply by 100. So to get from the rate as a % to the factor, we reverse... show more
    Best answer: I think your first row's Growth/Decay rate as a % is wrong. If the factor is 2.47, it's an increase of 147% (basically, subtract 1, then multiply by 100. This pattern is followed in the second row, 3.43 compared to 243%, is to subtract 3.43 by 1 and then multiply by 100. So to get from the rate as a % to the factor, we reverse the steps: Start with rate as a percent, divide by 100, then add 1. So starting with: 34.94% divide by 100 to get: 0.3494 Then add 1: 1.3494 If this is to be rounded to 2DP, you'd have: 1.35
    1 answer · Mathematics · 7 days ago
  • Trigonometry help?

    Best answer: You are given a right triangle with a known angle, known hypotenuse, and an unknown adjacent length. You can use cosine to solve for the unknown length: cos() = adj/hyp cos(55) = x / 72 0.573576 = x / 72 x = 41.2975 So rounded to the nearest whole, the answer is: 41 in.
    Best answer: You are given a right triangle with a known angle, known hypotenuse, and an unknown adjacent length. You can use cosine to solve for the unknown length: cos() = adj/hyp cos(55) = x / 72 0.573576 = x / 72 x = 41.2975 So rounded to the nearest whole, the answer is: 41 in.
    1 answer · Mathematics · 1 week ago
  • Calc question?

    Best answer: For a, you are given the equations, so just substitute and solve: (920 + 2x - 0.02x² + 0.00007x³) / 100 (920 + 2 * 100 - 0.02 * 100² + 0.00007 * 100³) / 100 (920 + 200 - 0.02 * 10000 + 0.00007 * 1000000) / 100 (1120 - 200 + 70) / 100 990 / 100 $9.90 per toy average when 100 are produced. ----------------- Find the marginal cost, so... show more
    Best answer: For a, you are given the equations, so just substitute and solve: (920 + 2x - 0.02x² + 0.00007x³) / 100 (920 + 2 * 100 - 0.02 * 100² + 0.00007 * 100³) / 100 (920 + 200 - 0.02 * 10000 + 0.00007 * 1000000) / 100 (1120 - 200 + 70) / 100 990 / 100 $9.90 per toy average when 100 are produced. ----------------- Find the marginal cost, so C'(100). So first, find C'(x) (the first derivative): C(x) = 920 + 2x - 0.02x² + 0.00007x³ C'(x) = 2 - 0.04x + 0.00021x² C'(100) = 2 - 0.04(100) + 0.00021(100)² C'(100) = 2 - 4 + 0.00021(10000) C'(100) = 2 - 4 + 2.1 C'(100) = 0.1 The marginal cost when 100 toys are produced is 10 cents. For part c, You are asked to solve for C(101) - C(100), which should be close to C'(100): C(101) - C(100) [920 + 2(101) - 0.02(101)² + 0.00007(101)³] - [920 + 2(100) - 0.02(100)² + 0.00007(100)³] [920 + 202 - 0.02(10201) + 0.00007(1030301)] - [920 + 200 - 0.02(10000) + 0.00007(1000000)] (920 + 202 - 204.02 + 72.12107) - (920 + 200 - 200 + 70) 990.10107 - 990 0.10107 Rounded to the nearest penny, a 10 cent difference.
    1 answer · Mathematics · 1 week ago
  • State the range of values of 𝑥 for which the quadratic inequality 𝑥2 −6𝑥 ≥ 0.?

    Best answer: x² - 6x ≥ 0 If we factor out the x, we get: x(x - 6) ≥ 0 So values that are equal to zero are in the solution set. This gives us 0 and 6. We are also looking for values that are greater than zero (aka: positive), so let's look at the ranges around our two values: if x > 6 we have positive times positive, which is positive,... show more
    Best answer: x² - 6x ≥ 0 If we factor out the x, we get: x(x - 6) ≥ 0 So values that are equal to zero are in the solution set. This gives us 0 and 6. We are also looking for values that are greater than zero (aka: positive), so let's look at the ranges around our two values: if x > 6 we have positive times positive, which is positive, in our solution set. if 0 < x < 6 we have positive times negative, which is negative, not in our solution set. if x < 0 we have negative times negative, which is positive, in our solution set. So including the zeros, your answer is: x ≤ 0 and x ≥ 6
    2 answers · Mathematics · 1 week ago
  • By doing rational zeros, I find out the roots of 3x^3+17x^2+21x-9 are 1/3 and -3.?

    Best answer: Let's start with this expression equal to 0 to make a function, since you are trying to solve for the zeroes: 3x³ + 17x² + 21x - 9 = 0 The Rational Root Therorm states that any rational roots will be a factor of the constant term (-9) over a factor of the high-degree coefficient (3), so your possible options are: ±1, ±3, ±9, ±1/3... show more
    Best answer: Let's start with this expression equal to 0 to make a function, since you are trying to solve for the zeroes: 3x³ + 17x² + 21x - 9 = 0 The Rational Root Therorm states that any rational roots will be a factor of the constant term (-9) over a factor of the high-degree coefficient (3), so your possible options are: ±1, ±3, ±9, ±1/3 (±3/3 and ±9/3 create duplicates of ±1 and ±3, so we don't have to include them again). So we have 8 possible options. It's possible that none of them are roots, or up to 3 of them could be. It's time to brute force check the 8 values since we know that two of them should be, and they are in the list of possible rational roots, I'll test them: 3x³ + 17x² + 21x - 9 3(1/3)³ + 17(1/3)² + 21(1/3) - 9 and 3(-3)³ + 17(-3)² + 21(-3) - 9 3(1/27) + 17(1/9) + 21/3 - 9 and 3(-27) + 17(9) - 63 - 9 3/27 + 17/9 + 21/3 - 9 and -81 + 153 - 63 - 9 1/9 + 17/9 + 63/9 - 81/9 and 0 0/9 and 0 0 and 0 So both of them are roots. Which leaves one left to find. We can turn each root into a factor, then multiply both factors together to get a quadratic which will also be a factor, then divide that from the original polynomial to get a linear expression remaining, which will tell us what the final root is: Known roots are: x = -3 and x = 1/3 So the factors are: (x + 3)(3x - 1) Multiply them together: 3x² - x + 9x - 3 3x² + 8x - 3 Now divide that by the original expression: . . . . . . . . . __x_+_3_____________ 3x² + 8x - 3 ) 3x³ + 17x² + 21x - 9 . . . . . . . . . . 3x³ + 8x² - 3x . . . . . . . . ---------------------------- . . . . . . . . . . . . . . . . 9x² + 24x - 9 . . . . . . . . . . . . . . . . 9x² + 24x - 9 . . . . . . . . . . . . . . . ------------------------ . . . . . . . . . . . . . . . . . . . . . . . . . 0 So the third root is also -3. The fully factored form of your original equation is: (3x - 1)(x + 3)² = 0 And your roots are: x = -3 and 1/3
    3 answers · Mathematics · 1 week ago
  • When i download a game from playstation now can i play it even after my subscription ends?

    Best answer: No. It requires continual membership to the program to continue playing it.
    Best answer: No. It requires continual membership to the program to continue playing it.
    2 answers · PlayStation · 1 week ago
  • What is the order of operations?

    Best answer: Perform any operations within parenthesis first (and if there are nested parenthesis, work from the inside set outward. Then resolve any exponents (square roots can count as both an exponent and parenthesis if a longer expression is under the radical) Then handle any multiplication and division at the same step, in order from left to... show more
    Best answer: Perform any operations within parenthesis first (and if there are nested parenthesis, work from the inside set outward. Then resolve any exponents (square roots can count as both an exponent and parenthesis if a longer expression is under the radical) Then handle any multiplication and division at the same step, in order from left to right Then any addition and subtraction at the same step, in order from left to right.
    2 answers · Mathematics · 1 week ago
  • Rational Equations word problems?

    Best answer: Let x = number of people on the tour. We know the cost is $1200, so the average cost per person is the expression: 1200 / x If we add 4 more people, at the same total cost, the average is reduced by $15. So the average cost per person if you add 4 more people is: 1200 / (x + 4) And that is $15 less than the original: 1200 / x -... show more
    Best answer: Let x = number of people on the tour. We know the cost is $1200, so the average cost per person is the expression: 1200 / x If we add 4 more people, at the same total cost, the average is reduced by $15. So the average cost per person if you add 4 more people is: 1200 / (x + 4) And that is $15 less than the original: 1200 / x - 15 Set them equal and solve for x: 1200 / (x + 4) = 1200 / x - 15 Let's start with dividing both sides by 15 to simplify the equation a little: 80 / (x + 4) = 80 / x - 1 Now multiply both sides the LCD, which is x(x + 4): 80x = 80(x + 4) - x(x + 4) Simplify this to a quadratic and solve: 80x = 80x + 320 - x² - 4x 0 = 320 - x² - 4x 0 = -x² - 4x + 320 I don't like having a leading coefficient that is negative, so I'll multiply both halves by -1, then I'll solve this by completing the square, so I'll add 320 to both sides: 0 = x² + 4x - 320 320 = x² + 4x Adding 4 to both sides, then we can factor the right side: 324 = x² + 4x + 4 324 = (x + 2)² Square root of both sides: ±18 = x + 2 Subtracting 2 from both sides: x = -20 and 16 We can't have a negative number of people paying a negative amount, so throw that out, leaving: 16 people initially signed up for the bus tour.
    1 answer · Mathematics · 1 week ago
  • I have games I play on my ohone?

    Best answer: Sounds scamish. I'd change your paypal password.
    Best answer: Sounds scamish. I'd change your paypal password.
    1 answer · Video & Online Games · 2 weeks ago
  • What was the last video game you played?

    Best answer: I was playing Spider-Man on PS4 last night.
    Best answer: I was playing Spider-Man on PS4 last night.
    33 answers · Video & Online Games · 2 weeks ago
  • I can't seem to get this problem right, could anyone help me understand it?

    Best answer: the equation you need to find this is Binomial Distribution: P(x) = N! / [x! (N - x)! p^x (1 - p)^(N - x) Where: p is the probability of the event happening N is the total number of attempts x is the number of attempts you want it to match So we know that N = 12. At least 7 times, means that we'll have to use x = 7, 8, 9, 10,... show more
    Best answer: the equation you need to find this is Binomial Distribution: P(x) = N! / [x! (N - x)! p^x (1 - p)^(N - x) Where: p is the probability of the event happening N is the total number of attempts x is the number of attempts you want it to match So we know that N = 12. At least 7 times, means that we'll have to use x = 7, 8, 9, 10, 11, and 12 and add the results together (or the sum of the results of 0, 1, 2, 3, 4, 5, 6 then subtract that from 1) Now we need to find p. The ways to roll a 6 are: 1-5, 2-4, 3-3, 4-2, 5-1 5 ways out of 36 possibilities, so the probability is 5/36 Let's make a more specific equation using what we know with only one unknown (x): P(x) = 12! / [x! (12 - x)! (5/36)^x (31/36)^(12 - x) You'll want to use a calculator or spreadsheet for this, since we have to solve for P(x) multiple times. After setting one up, I get: P(7) = 0.000374 P(8) = 0.0000377 P(9) = 0.0000027 P(10) = 0.000000131 P(11) = 0.00000000383 P(12) = 0.0000000000515 Add them up and we get: 0.000415 (rounded to 6 DP) As a test, if we do 0-6, add them up, we should get 1 - 0.000415 (or 0.999585): P(0) = 0.16623 P(1) = 0.321736 P(2) = 0.285411 P(3) = 0.153447 P(4) = 0.055686 P(5) = 0.014371 P(6) = 0.002704 Add them up and we get: 0.999585 (which is exactly what we expected). So again, the answer to your question is: 0.000415
    2 answers · Mathematics · 2 weeks ago
  • How would you solve this algebra problem?

    Best answer: as written, you have: -x/3 - (1/4)x = 14 I would multiply both sides by 12 to get rid of the fractions: -4x - 3x = 168 -7x = 168 x = -24
    Best answer: as written, you have: -x/3 - (1/4)x = 14 I would multiply both sides by 12 to get rid of the fractions: -4x - 3x = 168 -7x = 168 x = -24
    7 answers · Mathematics · 3 weeks ago
  • How do you play pokemon go on pc?

    Best answer: You'd need an android emulator. But without the ability to walk around, if you want to "simulate" that, you'd have to spoof your GPS, which is against EULA of the game and can get you banned. If you want to play the game, I'd suggest you get a compatible device with a compatible data plan and play it as intended. show more
    Best answer: You'd need an android emulator. But without the ability to walk around, if you want to "simulate" that, you'd have to spoof your GPS, which is against EULA of the game and can get you banned. If you want to play the game, I'd suggest you get a compatible device with a compatible data plan and play it as intended.
    1 answer · PC · 4 weeks ago
  • How do you distribute an exponent to a fraction such that it is (a^i/b^j)^x/y?

    Best answer: If you have two factors (or a quotient) that is taken to a power, then every factor (or part of the quotient) gets that exponent. A few examples: (xy)^a and (x/y)^a becomes: x^a y^a and x^a / y^a If you have an exponent of an exponent, you get the product of the exponents, example: (a^x)^y = a^(xy) And in the case that the... show more
    Best answer: If you have two factors (or a quotient) that is taken to a power, then every factor (or part of the quotient) gets that exponent. A few examples: (xy)^a and (x/y)^a becomes: x^a y^a and x^a / y^a If you have an exponent of an exponent, you get the product of the exponents, example: (a^x)^y = a^(xy) And in the case that the exponent is a fraction, doesn't change anything. You still apply it to all factors and multiply by any pre-existing exponents. so: (5² / 3²)^(3/2) We apply the 3/2 power to both the 5² and the 3². Both cases we multiply the 3/2 by the pre-existing 2 to get a new exponent of 3: 5³ / 3³
    2 answers · Mathematics · 4 weeks ago
  • Maths Quadratics?

    Best answer: When the discriminant is zero, you have one root (or more specifically, both roots have the same value): So in a quadratic: ax² + bx + c = 0 The discriminant is: b² - 4ac So if we find an expression for your discriminant, set it equal to zero, then solve for the unknown, we get the answer you are looking for. Your equation is: 4x²... show more
    Best answer: When the discriminant is zero, you have one root (or more specifically, both roots have the same value): So in a quadratic: ax² + bx + c = 0 The discriminant is: b² - 4ac So if we find an expression for your discriminant, set it equal to zero, then solve for the unknown, we get the answer you are looking for. Your equation is: 4x² + 4kx + 9 = 0 The discriminant equation when equal to zero is: b² - 4ac = 0 Using a = 4, b = 4k, and c = 9, we get: (4k)² - 4(4)(9) = 0 16k² - 144 = 0 16k² = 144 k² = 9 k = ±3 so there are two values of k that meets this condition. You are told that k > 0, so we can throw out the negative value, resulting in: k = 3
    9 answers · Mathematics · 3 weeks ago
  • Will going from a phone with 898mb ram to 2gb ram get rid of lag?

    Best answer: It depends on if RAM is your bottleneck. If it's CPU, then you need a phone with a better CPU. It depends on what phone you have, what the problems are, and what phones you are looking at for replacements.
    Best answer: It depends on if RAM is your bottleneck. If it's CPU, then you need a phone with a better CPU. It depends on what phone you have, what the problems are, and what phones you are looking at for replacements.
    7 answers · Video & Online Games · 3 weeks ago