##Free for only one week!!(from 13th, June~19th, June,2011) From the publisher East2West!!##
Arithmetic game have two modes, one is "one minute game", and another is "20 questions game". In the "one minute game", you will try your best to calculate arithmetic questions as more as possible. In the "20 questions game" mode, you need to solve all the 20 arithmetic questions in the shortest time. It has a really good exercise of your left brain, have a try!

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