Question

Age (in years) of 6 children of two groups are recorded as below:

Age (in Years)
Group A	Group B
7	7
7	9
9	11
8	12
10	12
10	12

1. Find the mode and range for each group.
2. Find the range and mode if the two groups are combined together.

Answer 1

From the given table, age of children in group A = 7 yr, 7 yr, 9 yr, 8 yr, 10 yr, 10 yr

Age of children in group B = 7 yr, 9 yr, 11 yr, 12 yr, 12 yr, 12 yr

a. Mode in group A = 7 yr and 10 yr.  ...[∵ 7 yr and 10 yr occurs most frequent, i.e.2 times]

Range in group A = Maximum value – Minimum value

= 10 – 7

= 3

Mode in groups B = 12 yr   ...[∵ 12yr is the most frequent, i.e. 3]

Range in group B = Maximum value – Minimum value

= 12 – 7

= 5

b. If both groups are combined together 7, 7, 7, 9, 9, 11, 8, 12, 10, 12, 10, 12.

Mode = 7 and 12   ...[∵ 7 and 12 occurs most frequent, i.e. 3 times]

∴ Range = Maximum value – Minimum value

= 12 – 7

= 5