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How Old Am I? Poster
Age 14 to 16
Challenge Level 
21
Why?
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
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