Class X
Practice Question (Statistics)
Q1.Find the
mean of the following data ( By direct method) : Ans-25.2
Class interval
|
0-10
|
10-20
|
20-30
|
30-40
|
40-50
|
Frequency
|
8
|
12
|
10
|
11
|
9
|
Q2. The
arithmetic mean of the following frequency distribution is 25. Determine the
value of p. Ans – p=16
Class
|
0-10
|
10-20
|
20-30
|
30-40
|
40-50
|
Frequency
|
5
|
18
|
15
|
p
|
6
|
Q3.If the
mean of the following frequency distribution is 65.6 , find the missing
frequency f1 and f2 . (Ans – 12,3)
Class
|
10-30
|
30-50
|
50-70
|
70-90
|
90-110
|
110-130
|
Total
|
frequency
|
5
|
8
|
F1
|
20
|
F2
|
2
|
50
|
Q4.Data
regarding the weights of students of class X of a school is given below : (Ans
– 57.24 kg)
Weight ( in kg)
|
50-52
|
52-54
|
54-56
|
56-58
|
58-60
|
60-62
|
62-64
|
Number of students
|
18
|
21
|
17
|
28
|
16
|
35
|
15
|
Compute the
mean weight of the students. ( By assumed mean method)
Q5.Calculate
the arithmetic mean of the following frequency distribution using the step
–deviation method : (Ans-148.61)
Class interval
|
Frequency
|
0-50
|
17
|
50-100
|
35
|
100-150
|
43
|
150-200
|
40
|
200-250
|
21
|
250-300
|
24
|
Q6.Compute
the arithmetic mean for the following data . (Ans- 28.6)
Marks obtained
|
Frequency
|
Less than 10
|
14
|
Less than 20
|
22
|
Less than 30
|
37
|
Less than 40
|
58
|
Less than 50
|
67
|
Less than 60
|
75
|
Q7.Find the
arithmetic mean of the following frequency distribution; (Ans- 36.36)
Class
|
25-29
|
30-34
|
35-39
|
40-44
|
45-49
|
50-54
|
55-59
|
Frequency
|
14
|
22
|
16
|
6
|
5
|
3
|
4
|
Q8.Find the
median wage from the following data:
(Ans- Rs .868)
Wages (In Rs)
|
800-820
|
820-840
|
840-860
|
860-880
|
880-900
|
900-920
|
920-940
|
Number of workers
|
7
|
14
|
19
|
25
|
20
|
10
|
5
|
Q9.Find the
missing frequencies in the following frequency distribution table ,if N=100 and
median is 32. (Ans 9,16)
Marks
|
0-10
|
10-20
|
20-30
|
30-40
|
40-50
|
50-60
|
Total
|
Number of students
|
10
|
?
|
25
|
30
|
?
|
10
|
100
|
Q10.Compare
the modal ages of two groups of students appearing for an entrance examination
: (Ans-18.93,18.83)
Age ( in years)
|
16-18
|
18-20
|
20-22
|
22-24
|
24-26
|
Group A
|
50
|
78
|
46
|
28
|
23
|
Group B
|
54
|
89
|
40
|
25
|
17
|
Q11.The
following table gives production yield per hectare of wheat of 100 farms of a
village.
Production yield ( kg/ha)
|
40-45
|
45-50
|
50-55
|
55-60
|
60-65
|
65-70
|
No of farms
|
4
|
6
|
16
|
20
|
30
|
24
|
Change the
distribution to a ‘more than’ type distribution and drive its ogive.
Q12.The
table given below shows the frequency distribution of the scores obtained by
200 candidates in a CET examination. (Ans- 3756)
Score
|
200-250
|
250-300
|
300-350
|
350-400
|
400-450
|
450-500
|
500-550
|
550-600
|
No of candidates
|
30
|
15
|
45
|
20
|
25
|
40
|
10
|
15
|
Draw
cumulative frequency curves by using (i) ‘less than’ series and (ii) ‘More
than’ series. Hence find the median
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