Question

There are nine branches of Subway® in a local area. Each day the manager takes a “mid-day read” of store sales in the area. One day, the mid-day read for the nine stores is (in $) : [205, 220, 105, 140, 190, 105, 190, 200, 115] .

Find the variance and standard deviation

Answer 1

	X
	205	1736.111 ( 205 - 163.333)2
	220	3211.111 ( 220 - 163.333)2
	105	3402.778 ( 105 - 163.333)2
	140	544.444   ( 140 - 163.333)2
	190	711.111   ( 190 - 163.333)2
	105	3402.778  ( 105 - 163.333)2
	190	711.111 ( 190 - 163.333)2
	200	1344.444 ( 200 - 163.333)2
	115	2336.111 ( 115 - 163.333)2
Total	1470	17400

Variance

= 1933.333

Standard Deviation