xwhere each x_{0}2^{0}+ x_{1}2^{1}+ x_{2}2^{2}+ x_{3}2^{3}

When x_{n} = 1, the corresponding age is in the column headed
2^{n}.

When x_{n} = 0, the corresponding age is *not* in the column headed
2^{n}.

Example: If you are 13 years old, your age will appear in the last three columns because

13 = 1^{.}2^{0}+ 1^{.}2^{1}+ 0^{.}2^{2}+ 1^{.}2^{3}= 8 + 4 + 0 + 1

Source: Berrondom, Marie

Categories: Number sense, Magic, Bases, Modular arithmetic, Favorite

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