Stage: 2 Challenge Level: 
What is the earliest time it could be?
How do you know?
What is the latest time it could be?
How do you know?
Can you get any closer?
How do you know?
What is the latest time it could be?
How do you know?
Can you get any closer?
Length/distance. Multiplication & division. Clock. Trial and improvement. Addition & subtraction. Combinations. Working systematically. Speed. Time. Angles.
Published January 2000,January 2009.
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