Selina solutions concise maths class 9 icse Solutions for Chapter 18 chapter 18 statistics

State, which of the following variables are continuous and which are discrete:

a) Number of children in your class

b) Distance traveled by car.

c) Size of shoes

d) Time

e) The number of patients in a hospital.

Given below are the marks obtained by 30 students in an examination:

08 17 33 41 47 23 20 34

09 18 42 14 30 19 29 11

36 48 40 24 22 02 16 21

15 32 47 44 33 01

Taking class intervals 1-10, 11-20, …., 41-50; make a frequency table for the above distribution.

Find the actual lower class limits, upper-class limits, and the mid-values of the classes:

10-19, 20-29, 30-39 and 40-49.

Construct the frequency distribution table from the following cumulative frequency table:

Ages No.of Students

Below 4 0

Below 7 85

Below 10 140

Below 13 243

Below 16 300

(i) State the number of students in the age group 10-13.

(ii) State the age-group which has the least number of students.

The value of ? up to 50 decimal places is:

3.14159265358979323846264338327950288419716939937510

(i) Make a frequency distribution table of the digits from 0 to 0 after the decimal place.

(ii) Which are the most and the least occurring digits?

Construct a combined histogram and frequency polygon for the following frequency distribution:

Construct a frequency polygon for the following data:

The daily wages in a factory are distributed as follows:

Draw frequency polygons for each of the following frequency distribution;

(a) Using histogram

(b) Without using histogram

(i)

(ii)