For the following table displays the heights (in inches) of students enrolled in an elementary school and the corresponding frequency; the sample mean for the table is 46.52 inches.

Use the formulas for grouped data to approximate the sample standard deviation. Enter exact values in the table (integers or decimals - no rounding). Round the variance and the standard deviation to the nearest hundredth.

Height (in inches)	Class Midpoint X	# students frequency, f
40-42	41	11
43-45	44	9
46-48	47	12
49-51	50	13
52-54	53	5

=

sample variance =

sample st dev =