Count On


Puzzle of the Day

These puzzles are also printed in Eight days a week, a booklet published by the Association of Teachers of Mathematics.The Association of Teachers of Mathematics

On a calculator try multiplying a number by itself several times and write down the answers. For instance 7 x 7 = 49, 7 x7 x 7 = 343, continue until you see a pattern in the last digit of the answer. If 7 was written 100 times with multiplication signs between them can you predict what the answer would end in?

Answer: ends in 1

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