CBSE Notes, Lectures

CBSE - Mathematics - Statistics

Statistics

NCERT Exercise Exercise 14.2

A company manufactures car batteries of a particular type. The lives (in years) of 40 such batteries were recorded as follows:

2.6 3.0 3.7 3.2 2.2 4.1 3.5 4.5

3.5 2.3 3.2 3.4 3.8 3.2 4.6 3.7

2.5 4.4 3.4 3.3 2.9 3.0 4.3 2.8

3.5 3.2 3.9 3.2 3.2 3.1 3.7 3.4

4.6 3.8 3.2 2.6 3.5 4.2 2.9 3.6

Construct a grouped frequency distribution table for this data, using class intervals of size 0.5 starting from the intervals 2 - 2.5.

A grouped frequency table of class size 0.5 has to be constructed, starting from class interval 2 - 2.5.

Therefore, the class intervals will be 2 - 2.5, 2.5 - 3, 3 - 3.5…

By observing the data given above, the required grouped frequency distribution table can be constructed as follows.

Lives of batteries (in years)

Number of batteries

2 - 2.5

2

2.5 - 3.0

6

3.0 - 3.5

14

3.5 - 4.0

11

4.0 - 4.5

4

4.5 - 5.0

3

Total

40

.