Respuesta :

20₃ - 11₃ = 20₃ - 10₃ - 1₃

… = 10₃ - 1₃

… = 2₃

Put another way, we "borrow a 1" from the 3¹ digits place:

20₃ = 1(3)₃ - 11₃ = 2₃

But this is just the number 2 (in base 10), which in base 2 would be 10₂.

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