Statistics Test...

Let $$x_i$$ represents the outcome on a fair die and $$f_i$$ be the corresponding frequency. The variance for random variable $$x_i$$ with following frequency distribution, is

If the sum of mean and variance of binomial distribution is 4.8 for 5 trials then

The mean deviation about the mean of the set of first $$n$$ natural numbers when $$n$$ is an odd number.

Let $$\sigma^{2}$$ is variance of following frequency distribution 

The sum of first $$n$$ natural numbers is given by the expression $$(2n^{2}+3n)$$. The mean of the given numbers is 

If the sum and sum of squares of $$10$$ observations are $$12$$ and $$18$$ resp., then, The $$S.D$$ of observations is :-

The mean and variance of a random variable having a binomial distribution are $$4$$ and $$2$$ respectively , then $$P(X=1)$$ is 

The mean and the standard devition (s.d) of five observations are $$9$$ and $$0$$, respecively. If one of the observations is changed such that the mean of the new set of five obervatons becomes $$10$$, then their s. d. is:

Let $$x_{1},\ x_{2},...x_{100}$$ are $$100$$ above observation such that $$\displaystyle \sum { { x }_{ 1 }=0 } ,\ \displaystyle \sum _{ 1\le i<j\le 100 }^{  }{ \left| { x }_{ i }{ x }_{ j } \right| =80000 } $$ & mean deviation from their mean is $$5$$, then their standard deviation, is- 

Mean derivation of the numbers $$1, 2, 3,...$$