# Lesson Notes By Weeks and Term - Senior Secondary School 2

PRESENTATION OF DATA

SUBJECT: MATHEMATICS

CLASS:  SS 2

DATE:

TERM: 3rd TERM

REFERENCE BOOKS

• New General Mathematics SSS2 by M.F. Macrae etal.
• Essential Mathematics SSS2 by A.J.S. Oluwasanmi.
• Exam Focus Mathematics.

WEEK FIVE

TOPIC: PRESENTATION OF DATA

• Cumulative Frequency Table.
• Cumulative Frequency Curve.

Cumulative Frequency Curve

The cumulative frequency curve is also called the OGIVE. It is the graph of the cumulative frequency against the upper class boundary.

Example

The table below shows the height of 200 people who were randomly picked.

 Heights(cm) 145  -     149 150    -    154 155     -   159 160       -    164 165    -    169 170  -   174 175   -  179 Frequency 5 18 50 29 80 14 4

Construct for the distribution above, a cumulative frequency curve.

Solution:

 Heights Frequency Cumulative Frequency Upper Class Boundary 145 – 149 5 5 < 149.5 150 – 154 18 23 < 154.5 155 – 159 50 73 < 159.5 160 – 164 29 102 < 164.5 165 – 169 80 182 < 169.5 170 – 174 14 196 < 174.5 175 – 179 4 200 < 179.5

EVALUATION

The table shows the masses of a various quantities of maize sold by a farmer during the year 1985.

 Mass (kg) 40    -    43 44    -    47 48      -   51 52    -    55 56    -     59 60    -    63 64   -67 68   - 71 Frequency 7 18 32 48 41 28 17 19
1. Draw a cumulative frequency table. (b) Using a scale of 2cm to 4 kg on the x – axis and 2cm to 20units on the y – axis, draw the cumulative frequency curve.

GENERAL EVALUATION

Given the frequency distribution below. Draw a histogram and a cumulative frequency curve.

 Height (cm) 160     -  164 165  -    169 170   - 174 175  - 179 180   -  184 185   -  189 190   - 194 Frequency 10 25 40 56 44 20 5

New General Mathematics SSS2, page164, exercise 14b.

WEEKEND ASSIGNMENT

The following table shows the distribution of the masses of 120 logs of wood, correct to the nearest kg.

 Masses (kg) 15      -     24 25       -      34 35       -      44 45      -    54 55    -    64 Frequency 14 54 24 26 2
1. Draw a histogram for the distribution.
2. Make a cumulative frequency table for the distribution.
3. Draw a cumulative frequency curve for the distribution.
4. Use the graph to find the a. semi-interquartile range.b. 60th percentile.