In your head! Addition and Sub

Challenge the ranking in Challenge Mode.

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Try to do as much addition as possible within 10 seconds.
Try to do as much addition as possible without making any mistakes!
Each has its own ranking. Let's try to get to the top!

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Answer the questions and earn trophies!
For example, if you achieve a certain number of total answers, number of correct answers, and number of consecutive correct answers, you can get a trophy.

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The wrong answers are displayed in red.
You can see which parts you are weak at.

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