Analyze grouped data for the number of cars passing through a checkpoint over 32 days.

The problem involves analyzing grouped data for the number of cars passing through a checkpoint over 32 days. The "Number of cars" intervals are given as -10, -20, etc. Assuming these are midpoints of class intervals and ignoring the negative signs (as car counts cannot be negative), we interpret the data as follows:

Number of cars (Midpoint, $x$)	Frequency (Number of days, $f$)	Class Interval	$fx$	$fx^2$	Cumulative Frequency (CF)
10	2	5-15	2