Operation 99 makes math fast and fun. Add...subtract! Can you last 99 seconds?
Sharpen your mental math skills with Operation 99! Choose an operation - either addition or subtraction - and test your speed on solving each problem. Tap the number tiles to add or subtract their values respectively. You have 10 seconds to solve each problem correctly.The problems are endless, how many can you get correct?
Can you last 99 seconds?
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