Setting Conditions : Less Than or Equal To

Author:
Lew W.S.
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This poster shows the luggage allowance for passengers with Economy class air tickets. To avoid paying for additional charges,  your luggage should not exceed 30 kg. Let us use the letter w  to represent the mass of the luggage in kilograms.

We say w is to be less than or equal to 30

We say w is to be less than or equal to 30
Notice w is on the left side (lesser) and 30 is on the right side.   Note w can be allowed to be equal to 30. Here's a closer look at the symbol for  "less than or equal to"  "lesser" on the left,  a line __ for "equal to" in the middle ! 
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