The following are the marks obtained by 40 students in an English examination (out of 50 marks). Draw a histogram and frequency polygon for the data

29, 45, 23, 40, 31, 11, 48, 11, 30, 24, 25, 29, 25, 32, 31, 22, 19, 49, 19, 13,32, 39, 25, 43, 27, 41, 12, 13, 32, 44, 27, 43, 15, 35, 40, 23, 12, 48, 49, 18.

GIVEN. Total number of students = 40

Maximum marks = 50

⇒ First make the table by above observation in specific

Interval

Total number of values = 50

Range = Highest – Lowest

= 49 – 11

= 38

Let’s Divide data in 4 class intervals

10-20, 20-30, 30-40, 40-50

⇒ Draw histogram of given table

As the data is in continuous form

⇒ Mark class interval along X axis on uniform scale

⇒ Mark frequency along Y axis on uniform scale

⇒ Construct rectangles with class intervals as base and

corresponding frequencies as height.

⇒ Take out the midpoints of each interval

Imagine 2 midpoints at 1^st and last of 0 frequency join all midpoints and imaginary midpoints to get frequency polygon.