"How Divine Is My Proportion?"

Edwina R. Justice Gunsaulus Scholastic Academy
4420 South Sacramento Ave.
Chicago IL 60632
(312) 535-7215

Objectives (Staff):

Demonstrate a phenomenological approach to teaching mathematics.

Inspire others to use the approach.

Objectives (Grade 8):

Relate the ratio of successive numbers in the Fibonacci Sequence to the
"divine proportion".

Compare approximate golden rectangles to human body proportions.


Measure in advance and select items whose sides are in the approximate ratio of

file cards (assorted sizes) envelopes charge plates photos
greeting cards (assorted sizes) invitations pamphlets books

Recommended Strategy:

Measure items and calculate the ratio of longest side divided by shortest

List quotients on the chalkboard and discuss similarities.

Measure the height and the distance from the top of the head to the middle
finger tip with an arm extended to one side. Calculate the ratio of the two

Compare the ratio of body measurements to the results obtained from other

Determine a pattern and complete a number sequence:

1, 1, 2, 3, 5, 8, 13, 21, ...
(Additional numbers are optional.)

Calculate the ratio of two successive numbers:

1/1, 2/1, 3/2, 5/3, 8/5, 13/8, 21/13

(The ratio 21/13 equals 1.6154 rounded to the nearest ten-thousandth
and represents the ratio of the sides of a golden rectangle.)

Compare the quotient of a golden rectangle ratio to ratios of selected items
and body proportions.

Students should look for golden rectangles and divine proportion
measurements at school, home and other places.

Return to Mathematics Index