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.

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

• 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

READING ASSIGNMENT

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.