Puzzle 92 - Perfect square

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1. The number 121 is a perfect square. In a decimal system. In which other number system, is 121 a perfect square?





 

 

 

 

 

Bonus : Let us look at another puzzle based on different bases.

2. What is the missing number in the following sequence: 10, 11, 12,13, 14, 15, 16, 17, 20, 22, 24, 31, 100, - - , 10,000. (Hint: The missing number is in ternary notation)

 Find the solutions to these puzzles here.

 

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