The monthly consumption of electricity (in units) of 50 consumers is given in the table below.

1. Write the formula to find the median of a continuous series.
2. Find the modal class and median class of the given data.
3. Calculate the median of the given data.
4. Did you find the modal class and median class same from the above computation? Are they always same? Give reason.

The weight of 20 students is presented here in the table.

1. In a continuous series, what does m represent in the formula ($\rm\overline X$)=$\rm \frac {\sum fm}{N}$ to calculate mean? Write it. 
2. Find the median class of the given data.
3. Calculate the average weight from the given data.
4. Is the class of measure of central tendencies of the given data same? Justify it.