Stage: 1 Challenge Level: 
Sam got into an elevator.
He went down five floors, up six floors, down seven floors, then got out on the second floor.
On what floor did he get on?
Working systematically. Factors and multiples. Addition & subtraction. Generalising. Comparing and Ordering numbers. Interactivities. Trial and improvement. Combinations. Multiplication & division. Investigations.
Published November 1999.
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