Tamil Nadu Board of Secondary EducationSSLC (English Medium) Class 10th

# The mean of 100 observations is 40 and their standard deviation is 3. The sum of squares of all deviations is - Mathematics

MCQ

The mean of 100 observations is 40 and their standard deviation is 3. The sum of squares of all deviations is

• 40000

• 160900

• 160000

• 30000

#### Solution

160900

Explanation;

Hint:

σ = 3

(sumx^2)/"n" - ((sumx)/"n")^2 = 9

(sumx^2)/100 - 40^2 = 9

(sumx^2)/100 = 9 + 1600

(sumx^2)/100 = 1609

sumx^2 = 160900

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#### APPEARS IN

Samacheer Kalvi Mathematics Class 10 SSLC Tamil Nadu State Board
Chapter 8 Statistics and Probability
Exercise 8.5 | Q 4 | Page 331