Please note the Excel files in this section use the
LCM & GCD functions which require Analysis ToolPak to have
been installed as part of Excel.
The Excel files Fraction Addition and
Fraction
Subtraction could be used simply to demonstrate and explain
addition and subtraction of fractions, however, practice and
reinforcement can frequently be accomplished successfully, and
abler pupils better motivated, if an approach of differentiation by
challenge is adopted. This means that the same resource is used
with all children but the challenge is varied for children at
different stages of understanding.
A suitable challenge for pupils who were becoming secure with the
basic concept of addition or subtraction of fractions would be:
Find two fractions that add up to 5/6 , which are not sixths, or
add up to 9/10, but not tenths, etc.
With children in pairs, each pupil can then invent similar puzzles
for their partner.
What about adds up to 7/15 but not fifteenths? Explore what can and
can't be done and why.