Page 1 - CH-15(XI) WORKSHEETS. (2)

WORKSHEETS,

CHAPTER-15,

STATISTICS

1. The mean deviation of the data 3,10,10,4,7,10,5 from the mean is

(a) 2 (b) 2.57 (c) 3 (d) 3.75

2. The standard deviation of data 6,5,9,13,12,8 and 10 is

52 52
(a) √ (b) (c)√6 (d) 6
7 7
−−−−−−−−−−
3. Coefficient of variation = × 100

4. The variance of data is 121, then standard deviation of data is ---------.

5. Find the mean deviation about the median for the data 34, 66, 30, 38, 44, 50, 40,

60, 42, 51.

6. Find the Variance & SD of first n natural number.

7. Coefficient of variation of two distribution are 60 & 70 and their standard deviations are 21
& 16

respectively, what are the arithmetic means.

8. The Sum & sum of squares corresponding to length x (in cm) & weight ( in gm) of 50 plant
product

2
2
are given as ∑ 50 = 212 , ∑ 50 = 902.8 & ∑ 50 =261, ∑ 50 =
=1

=1

=1
=1
1457.6
which is more varying the length or weight.
9. Find the Standard deviation & variance of following data.
Xi = 140 145 150 155 160 165 170 175.
Fi= 4 6 15 30 36 24 8 2