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How Old Am I? Poster

Age 14 to 16
Challenge Level





Adding 30 to the age 15 years ago is the same as squaring it

Number Square Difference
3 9 6
4 16 12
5 25 20
6 36 30
7 49 42

The difference keeps getting bigger so 6 is the only solution

I was 6 15 years ago, so now I am 21