1. The product of two odd numbers is 255.
What are they?
2. The difference between two square numbers is 21.
What are they?
3. The sum of three prime numbers is 17.
What are they?
4. The ratio of two even numbers is 3:5.
What are they?
Topics: Starter  Arithmetic  Number  Puzzles  Ratio
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1. 1 and 255 or 3 and 85 or 5 and 51 or 15 and 17 (and their negatives).
2. 4 and 25 or 100 and 121. Could there be any other solutions?
3. 2, 2 and 13 or 3, 3 and 11 or 3, 7 and 7 or 5, 5 and 7.
4. 6 and 10 or 12 and 20 or 18 and 30 or ...
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