The formula for Z-Score is: (x-mu)/sigma. We know from the information given that Z=0.5, mu=300 & sigma=100. Solve for x and plug in the values. X=Z*sigma+mu; x=0.5*100+300 or x=350. So, $350 is amount spent on books.
Z-score is the x value minus the mean, all divided by the standard deviation; or z=(x-mu)/sigma. The "x" value needs to be given to answer the question.
There are three sigma symbols, an upper case, a lower case and an end of the sentence case. The capital letter case is used as summation. The lower case is used to represent variance in statistics. The lower case is also used to represent stress in mechanics and physics. The end of sentence case is generally not used. Reference link: http://en.wikipedia.org/wiki/Sigma.
The z-score can't be calculated with the information given. A mean & standard deviation is required to put into the formula: Z = (x-mean)/sigma. Your x value is 10.
formula for finding mean through direct mean method: sigma fi xi /sigma fi
Since this is regarding statistics I assume you mean lower case sigma (σ) which, in statistics, is the symbol used for standard deviation, and σ2 is known as the variance.
It means the sum total.
Let x denote the values of the variable in question. Suppose there are n observations. Let Sx = the sum of all the values. then the mean of x, Mx = Sx/n Let Sxx = the sum of all the squares of the values. The Vx (= the variance of x) is Sxx - (Mx)^2 and sigma(x) = sqrt(Vx). Therefore one sigma deviation, relative to the mean, = Mx - sigma(x), Mx + sigma(x).
Coefficient of deviation (CV) is a term used in statistics. It is defined as the ratio of the standard deviation (sigma) to the mean (mu). The formula for CV is CV=sigma/mu.
z = (x - mean of x)/ std dev of x I thought this website was pretty good: http://www.jrigol.com/Statistics/TandZStatistics.htm
Sigma is used to represent the standard deviation of a dataset. The calculation is rather complex, but if you think of it as the "root of the mean of the squares of the differences" ... rms of differences ... it might make more sense.Enter "standard deviation" on you search engine of choice for details. Wikipedia has a couple of basic examples, and a whole lot more!Mu represents the population mean, or "average" - add all the values and divide by how many.In statistics, you often don't know the population mean, so you take samples and find "x bar", the sample means, then using those to calculate an estimate of the population mean.
in statistics, summation denoted by upper case sigma, is used to find the sum of a series of observation in a particular variable.
X=46
z=x-mean / sd
If X and Y are independent Gaussian random variables with mean 0 and standard deviation sigma, then sqrt(X^2 + Y^2) has a Rayleigh distribution with parameter sigma.
Quantitive Skills
The formula for Z-Score is: (x-mu)/sigma. We know from the information given that Z=0.5, mu=300 & sigma=100. Solve for x and plug in the values. X=Z*sigma+mu; x=0.5*100+300 or x=350. So, $350 is amount spent on books.