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Age 11 to 14 Short
Challenge Level
77 is multiplied by another two-digit number with identical digits.
The third digit of the product, counting from left to right, is a 3.
What is the product?
This problem is adapted from the World Mathematics Championships
You can find more short problems, arranged by curriculum topic, in our short problems collection.
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NRICH is part of the family of activities in the Millennium Mathematics Project.
NRICH is part of the family of activities in the Millennium Mathematics Project.