Question

# Find the mean deviation from the mean and from median of the following distribution : Marks0−1010−2020−3030−4040−50No. of students5815166

Open in App
Solution

## Computation of M.D.from Median MarksStudentsxiCum.Freq.|di|=|xi−28|fidifixi|xi−27|fi|xi−27|0−1055523115252211010−208151313104120129620−3015252834537523030−401635447112560812840−50645501710227018108∑5i=1fidi=478T=1350∑8i=1fi|xi−27|=472 N=50,N2=25 The cumulative frequency just greater than N2=25 is 28 and the corresponding class is 20 - 30 Thus the median class is 20 - 30 Using formula ∴l=20, F=13, f=15, h=10 Median =l+N2−Ff×h Substituting the values Median =20+25−1315×10=20+8=28 Mean distribution on from the median =∑5i=1fi|di|N=47850=9.56 Mean (¯X)=∑5i=1fixiN=135050=27 M.D. from the mean =150×∑5i=1fi|xi−27|=47250=9.44 M.D. from the mean are 9.56 and 9.44 respectively.

Suggest Corrections
0
Related Videos