SUBJECT: History of Mathematics TOPIC: Arithmetic in the Ancient World
REPORTER: Barrera, Melmarie D. SUBTOPIC: Egyptian Fraction
COURSE AND YR: BSE-Math 1 INSTRUCTOR: Ms. Myra Leonor Mon
EGYPTIAN FRACTION
An Egyptian fraction is a sum of positive (usually) distinct unit fraction. The famous RHIND
PAPYRUS dated to around 1650 BC contains a table of representation of as Egyptian fraction.
➢ The Egyptians of 3000 BC had an interesting way to represent fractions. Although they had a
notation for ½, 1/3, ¼ and so on (these are called reciprocals or unit fractions, since they are 1/n for
some number n) their notation did not allow to write 2/5, ¾, 4/4, 5/7 etc. They were able to write any
fraction as a sum of unit fractions were different.
EXAMPLE:
𝟓 𝟏 𝟏
𝟏. = +
𝟖 𝟐 𝟖
How to solve? (TRIAL AND ERROR)
Note: The given example we can possibly multiply it by (2/2, 3/3,4/4,5/5 and so on.). It depends
on the given example.
5/(8 ) (2/2)= 10/16 (1*16), (2*8), (4*4), (8*2), (16*1)
o Find the numbers that multiplies of the denominator:
Result (1,2,4,8,16)
o After of finding the number that multiplies of denominator.
Get the total of numerator in the result in multiplies of denominator.
(2+8=10)
Therefore:
2/16 + 8/(16. ) = (10 )/(16 )
Recheck:
2/16+8/16= (2+8)/16 = 10/16 reduce it by the lowest term 1/8+1/2=10/16
o After of rechecking of the result, finalize your answer by sequencing it from least to greatest
denominator.
ANSWER: 5/8= 1/2+1/8
➢ A fraction written as a sum or distinct unit fractions is called an Egyptian Fraction.
Rules in Egyptians Fractions or Unit Fractions
❖ A unit fraction is a rational number that can be written as a fraction where the numerator is one and
the denominator is a positive integer.
❖ A unit fraction is reciprocal of a positive integer, 1/n. Examples are 1/2, 1/3, 1/4 ,1/5, etc.
❖ 1/1 = is an improper unit fraction.
❖ 1/2, 1/3,1/4, 1/5, etc.… … is a proper unit fraction
❖ A unit fraction is a fraction with 1 in the numerator, such as ½ or ¼.
❖ They would write ¾ as ½ + ¼.
❖ They would not write ¾ as ¼ + ¼ + ¼ because these addends are not distinct, so all of the
denominators are need to be different but all of the numerators need to be equal to 1.
❖ Writing a fraction as the sum of distinct unit fractions was a natural extension that came from a
process for dividing.
❖ It is also useful for comparing fractions and order them from least to greatest (or vice versa).