Direct Variation or "is proportional to"
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LESSON PLAN
DIRECT VARIATION
Class: Form 4 or 5
Duration: A double period (90 mins)
Objectives
At the end of this lesson the student should be able to:

Definition
Direct Proportionality
Two quantities x and y are said to be related by a direct proportionality if an increase in x by a factor will lead to an increase in y by exactly the same factor. 