• I need help with telecommunications homework problem?

    It is necessary to transmit the human voice using a frequency range from 300 Hz to 3.5 kHz using a digital system. (a) What is the minimum required sampling rate, according to theory? (b) Why would a practical system need a higher rate than the one you calculated in part (a)?
    It is necessary to transmit the human voice using a frequency range from 300 Hz to 3.5 kHz using a digital system. (a) What is the minimum required sampling rate, according to theory? (b) Why would a practical system need a higher rate than the one you calculated in part (a)?
    2 answers · Engineering · 6 years ago
  • Help with central limit theorem in statistics?

    Among the adults in a large city, 30% have a college degree. A simple random sample of 100 adults is chosen. What is the probability that more than 35 of them have a college degree?
    Among the adults in a large city, 30% have a college degree. A simple random sample of 100 adults is chosen. What is the probability that more than 35 of them have a college degree?
    1 answer · Mathematics · 7 years ago
  • Help with Standard deviation in statistics?

    A gas station earns $2.60 in revenue for each gallon of regular gas it sells, $2.75 for each gallon on midgrade gas, and $2.90 for each gallon of premium gas. Let X1, X2, and X3 denote the numbers of gallons of regular, midgrade, and premium gasoline sold in a day. Assume that X1, X2, and X3 have means μ1 = 1500, μ2 = 500, and μ3 = 300, and standard... show more
    A gas station earns $2.60 in revenue for each gallon of regular gas it sells, $2.75 for each gallon on midgrade gas, and $2.90 for each gallon of premium gas. Let X1, X2, and X3 denote the numbers of gallons of regular, midgrade, and premium gasoline sold in a day. Assume that X1, X2, and X3 have means μ1 = 1500, μ2 = 500, and μ3 = 300, and standard deviations σ1 = 180, σ2 =90, and σ3 = 40. a.) Assuming X1, X2, and X3 to be independent, find the standard deviation of the daily revenue.
    2 answers · Mathematics · 7 years ago
  • Help with statistics random variables?

    After manufacture, computer disks are tested for errors. Let X be the number of errors detected on a randomly chosen disk. The following table presents values of the cumulative distribution function F(x) of X. x F(x) 0 0.41 1 0.72 2 0.83 3 0.95 4 1.00 a) What is the probability that two or fewer... show more
    After manufacture, computer disks are tested for errors. Let X be the number of errors detected on a randomly chosen disk. The following table presents values of the cumulative distribution function F(x) of X. x F(x) 0 0.41 1 0.72 2 0.83 3 0.95 4 1.00 a) What is the probability that two or fewer errors are detected? b) What is the probability that no errors are detected?
    2 answers · Mathematics · 7 years ago
  • Help with voltage divider rule?

    An electrical load has a power factor of 0.8 lagging. It dissipates 8 kW at a voltage of 200 V. Calculate the impedance of this load in rectangular coordinates.
    An electrical load has a power factor of 0.8 lagging. It dissipates 8 kW at a voltage of 200 V. Calculate the impedance of this load in rectangular coordinates.
    1 answer · Engineering · 7 years ago
  • Help with a statistics problem in conditional probability & independence?

    Of all failures of a certain type of computer hard drive, it is determined that in 20% of them only the sector containing the file allocation table is damaged, in 70% of them only nonessential sectors are damaged, and in 10% of the cases both the allocation sector and one or more nonessential sectors are damaged. A failed drive is selected at random... show more
    Of all failures of a certain type of computer hard drive, it is determined that in 20% of them only the sector containing the file allocation table is damaged, in 70% of them only nonessential sectors are damaged, and in 10% of the cases both the allocation sector and one or more nonessential sectors are damaged. A failed drive is selected at random and examined. 1) If the drive is found to have a damaged allocation sector, what is the probability that some nonessential sectors are damaged as well? 2) If the drive is found to have a damaged allocation sector, what is the probability that NO nonessential sectors are damaged? For the first problem I got 0.875 but not sure if that's correct and for the second problem I don't know how to figure it out because it is asking for no nonessential sectors damaged?
    2 answers · Mathematics · 7 years ago
  • I need help with a statistics problem in conditional probability & independence?

    The article "Integrating Risk Assessment and Life Cycle Assessment: A Case Study of Insulation" estimates that 5.6% of a certain population has asthma, and that an asthmatic has probability 0.027 of suffering an asthma attack on a given day. A person is chosen at random from this population. What is the probability that this person has an... show more
    The article "Integrating Risk Assessment and Life Cycle Assessment: A Case Study of Insulation" estimates that 5.6% of a certain population has asthma, and that an asthmatic has probability 0.027 of suffering an asthma attack on a given day. A person is chosen at random from this population. What is the probability that this person has an asthma attack on that day?
    2 answers · Mathematics · 7 years ago
  • Help with statistics counting method?

    In a certain state, license plates consist of three letters followed by three numbers. a. How many different license plates can be made? I think I got this part correctly. For this I did 26*26*26*10*10*10 = 17,576,000 because it's 26 letters and 10 digits. b. How many different license plates can be made in which no letter or... show more
    In a certain state, license plates consist of three letters followed by three numbers. a. How many different license plates can be made? I think I got this part correctly. For this I did 26*26*26*10*10*10 = 17,576,000 because it's 26 letters and 10 digits. b. How many different license plates can be made in which no letter or number appears more than once? c. A license plate is chosen at random. What is the probability that no letter or number appears more than once?
    2 answers · Mathematics · 7 years ago
  • Need help with capacitance?

    Find the capacitance of a parallel plate capacitor if the area of each plate is 0.1m^2 and the distance between the plates is 0.1 inch. The dielectric is air.
    Find the capacitance of a parallel plate capacitor if the area of each plate is 0.1m^2 and the distance between the plates is 0.1 inch. The dielectric is air.
    3 answers · Engineering · 7 years ago
  • First order linear differential equations help?

    I just have a single question about this differential equation. Use first order of linear differential equation to solve this problem: 2(dy/dx) = 5 - 6y I know the equation is (dy/dx) + P(x) y = Q(x) so my question is what do I do with the 2 that's in 2(dy/dx)? So far I did 2(dy/dx) + 6y = 5
    I just have a single question about this differential equation. Use first order of linear differential equation to solve this problem: 2(dy/dx) = 5 - 6y I know the equation is (dy/dx) + P(x) y = Q(x) so my question is what do I do with the 2 that's in 2(dy/dx)? So far I did 2(dy/dx) + 6y = 5
    3 answers · Mathematics · 7 years ago
  • First order linear differential equations help?

    How do I solve this differential equation using the first order linear differential equations? dy + 3ydx = e^(-3x) dx
    How do I solve this differential equation using the first order linear differential equations? dy + 3ydx = e^(-3x) dx
    3 answers · Mathematics · 7 years ago
  • Differential equations help?

    How do I solve this differential equation using separation of variables? Am I suppose to plug in the zeros for t and s? ds/dt = sec(s); t = 0 when s = 0
    How do I solve this differential equation using separation of variables? Am I suppose to plug in the zeros for t and s? ds/dt = sec(s); t = 0 when s = 0
    3 answers · Mathematics · 7 years ago
  • I need help with differential equations?

    How to solve this differential equation using separation of variables? 2dy/dx = y(x+1) / x
    How to solve this differential equation using separation of variables? 2dy/dx = y(x+1) / x
    3 answers · Mathematics · 7 years ago
  • Help with differential equations?

    I need help solving this differential equation using separation of variables: ydx + xdy = 3xydx
    I need help solving this differential equation using separation of variables: ydx + xdy = 3xydx
    3 answers · Mathematics · 7 years ago
  • Clock Signals and Clocked Flip-Flops help?

    A certain clocked FF has minimum ts = 20 ns and th = 5 ns. How long must the control inputs be stable prior to the active clock transition?
    A certain clocked FF has minimum ts = 20 ns and th = 5 ns. How long must the control inputs be stable prior to the active clock transition?
    3 answers · Engineering · 7 years ago
  • Help finding the radius of convergence?

    Find the radius of convergence (R), and the convergence interval, for the following power series: ∞ Σ (2^n / n!)(x - 1)^n ; (a = 1) n=0 So far I've gotten lim(n→∞) (2^(n+1)*((x-1)^(n+1)) / (n+1)!) * (n! / ((2^n)(x-1)^n)). I have no idea what to do after that.
    Find the radius of convergence (R), and the convergence interval, for the following power series: ∞ Σ (2^n / n!)(x - 1)^n ; (a = 1) n=0 So far I've gotten lim(n→∞) (2^(n+1)*((x-1)^(n+1)) / (n+1)!) * (n! / ((2^n)(x-1)^n)). I have no idea what to do after that.
    2 answers · Mathematics · 7 years ago
  • Help finding the radius of convergence?

    Find the radius of convergence (R), and the convergence interval, for the following power series: ∞ Σ (1/n)x^n n=0 I tried using the ratio test but can't figure out the radius of convergence
    Find the radius of convergence (R), and the convergence interval, for the following power series: ∞ Σ (1/n)x^n n=0 I tried using the ratio test but can't figure out the radius of convergence
    1 answer · Mathematics · 7 years ago
  • How to find the inverse of a diagonal matrix?

    Find A^-1 if A = [alpha, 0, 0] [0, beta, 0] [0, 0 , epsilon] I've looked online and notes that the answer is: [1/alpha, 0, 0] [0, 1/beta, 0] [0, 0, 1/epsilon] I want to know why. Examples on youtube and my notes do not explain the steps. All they say is that the inverse is 1 over the element.
    Find A^-1 if A = [alpha, 0, 0] [0, beta, 0] [0, 0 , epsilon] I've looked online and notes that the answer is: [1/alpha, 0, 0] [0, 1/beta, 0] [0, 0, 1/epsilon] I want to know why. Examples on youtube and my notes do not explain the steps. All they say is that the inverse is 1 over the element.
    4 answers · Mathematics · 7 years ago
  • Need help on a physics current problem?

    If a conductor with a current of 200 mA passing through it converts 40 J of electrical energy into heat in 30 s, what is the potential drop across the conductor?
    If a conductor with a current of 200 mA passing through it converts 40 J of electrical energy into heat in 30 s, what is the potential drop across the conductor?
    1 answer · Physics · 7 years ago
  • Can't download any apps in the Android market?

    I just got my Samsung Captivate Galaxy S phone yesterday and I created a Google account so I can download some applications but I can't seem to download anything. Whenever I want to download an application it would only say "starting downloading" for hours and not actually download. Also to add that I'm using Wi-Fi not 3G because I... show more
    I just got my Samsung Captivate Galaxy S phone yesterday and I created a Google account so I can download some applications but I can't seem to download anything. Whenever I want to download an application it would only say "starting downloading" for hours and not actually download. Also to add that I'm using Wi-Fi not 3G because I do not want to use my data. Is AT&T's severs down or is it my phone or google account?
    4 answers · Mobile Phones & Plans · 8 years ago