Stage: 3 and 4 Challenge Level: 
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The answer is 49.
What is the question?
Why does it work?
|
 |
The answer is 42.
What is the question?
Why does it work?
|
 |
The answer is 63.
What is the question?
Why does it work?
|
 |
The answer is 56.
What is the question?
Why does it work?
|
Does this always work?
Can you extend the method to other numbers?
Art. Making and proving conjectures. History of number systems. Multiplication & division. Patterned numbers. Famous mathematicians. Geometric sequence. Transformation of functions. Representing. History of mathematics.
Published April 2009.
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