The mean deviation about median from the data 340, 150, 210, 240, 300, 310, 320, is

Arranging the observations in ascending order of magnitude, we have 150, 210, 240, 300, 310, 320, 340. Clearly, the middle observation is 300.∴ Median= 300.Calculation of Mean Deviation34015021024030031032040150906001020∴ M.D.=1nΣdi=17Σxi−300=3707=52.8