Question 1 The heights of 60 students, measured to the nearest centimeters. The values are shown below
161 150 154 165 168 161 154 162 150 151
162 164 171 165 158 154 156 172 160 170
153 159 161 170 162 165 166 168 165 164
154 152 153 156 158 162 160 161 173 166
161 159 162 167 168 159 158 153 154 159
162 158 161 167 169 154 156 151 154 159
(i) Represent the data given above by a grouped frequency distribution table, taking the class intervals as 160  165, 165  170, etc.
(ii) What can you conclude about their heights from the table?
Solution
Grouped frequency distribution table for total students(60)
Height (cm) 
No of students 
150155 
15 
155160 
12 
160165 
16 
165170 
12 
170175 
5 
We can see that 70% of the students is having height less than 165
Question 2 The following number of goals were scored by a Indian hockey team in a series of 10 matches:
2, 3, 4, 5, 0, 1, 3, 3, 4, 3
Find the mean, median and mode of these scores
Solution
1) Arange then in ascending order
0,1,2,3,3,3,3,4,4,5
2) Frequency distribution
Mean=(0+1+2+3+3+3+3+4+4+5)/10=28/10=2.8
Median=3
Mode=3
Question 3 Three coins were tossed 30 times simultaneously. Each time the number of heads occurring was noted down as follows
0 1 2 2 1 2 3 1 3 0
1 3 1 1 2 2 0 1 2 1
3 0 0 1 1 2 3 2 2 0
Prepare a frequency distribution table for the data given above.
Solution By observing the data given above, the required frequency distribution table can be constructed as follows.
Number of heads

Number of times (frequency)

0

6

1

10

2

9

3

5

Total

30
