A group of 45 house owners contributed money towards green environment of their street. The amount of money collected is shown in the table below.

Calculate the variance and standard deviation.

Calculate the variance of the following data

The time (in seconds) taken by a group of people to walk across a pedestrian crossing is given in the table below.

Calculate the variance and standard deviation of the data.

Find the variance of the following distribution.

Mean of 100 items is 48 and their standard deviation is 10. Find the sum of all the items and the sum of the squares of all the items.