The length of class interval is the difference between two consecutive lower limits or  limits. $\left(\text{Lower/Upper/Mid}\right)$

The breadth of a rectangle in a histogram is proportional to the length of the _____. (class interval/ bar)

Calculate the mean:

Calculate the mean:

Find the median: $9,13,14,15,18, 21, 29$

Find the median: $11,4,19,8,10,8,10,14$

Write down the mode: $8,2,11,3,17,11,6,12$