It was written 21 instead of 12 when the mean of nine numbers are calculated.The mean obtained was 19. Then find out the mean when 12 istaken.

Find the mean of first 99 natural numbers.

The mean of the frequency table given below is 50.Then find out the values of a and b. .

If n arithmetic means are inserted between 2 and 38 then the sum of the resulting series is obtained as 200 . Then find the value of n.

In the given below table, the mean is 21.12, then find the value of k. .

The mean of 20 numbers is 22.Find out the mean of numbers if 3 is removed and 8 is added.

Choose the corréct answer in each of the following The mean of the numbers obtained on throwing a die having written 1 on three faces, 2 on two faces and 5 on one face is

In a class there are 20 boys and the remaining students are girls.The mean weights of the total 50 students is 23 kg. The mean weight of boys is 30.Then find out the mean weight of girls.

Find the mean and variance of the number obtained on a throw of an unbiased die.

Find the mean and variance of the number of heads in the two tosses of a coin.