Wizard

Tell any friend to pick a number from 1 to 21 (or 1 to 31 at the advanced level), but not to tell you.

Ask your friend in which of the 5 columns is the number he thought of. Once he tells you the columns where the number is, you can guess it.

LANGUAGES: English, Spanish, German, French, Italian, Portuguese, Chinese, Korean, Japanese and Russian.

IDEAL for boys and girls to exercise their minds while learning the binary addition system.

:::: DOES NOT CONTAIN ADS ::::