The variance of first 50 even natural numbers is Maths Questions, Statistics Questions / By mathemerize Solution : \({\sigma^2}\) = \(\sum(x_i – \bar{x})^2\over n\) \(\bar{X}\) = \(\sum x_i\over n\) = \(2 + 4 + 6 + 8 + ….. + 100\over 50\) = 51 \({\sigma^2}\) = \(2^2 + 4^2 + …. + 100^2\over 50\) – \(51^2\) = 833 Similar Questions The mean and variance of a random variable X having a binomial distribution are 4 and 2 respectively, then P(X = 1) is The median of a set of 9 distinct observations is 20.5. If each of the largest 4 observation of the set is increased by 2, then the median of the new is The mean and the variance of a binomial distribution are 4 and 2, respectively. Then, the probability of 2 success is In a series of 2n observations, half of them equals a and remaining half equal -a. If the standard deviation of the observation is 2, then |a| equal to All the students of a class performed poorly in mathematics. The teacher decided to give grace marks of 10 to each of the students. Which statistical measure will not change even after the grace marks were given ?