Extreme Addition vs Mathji Math Practice & Quizzes

Extreme Addition® is a unique and extraordinarily simple game that takes you into the world of extreme additions. You will love this game. You will boost your mental calculation and your mastery of numbers. You will gain speed of execution and reasoning. You will create automatisms. You will boost your concentration and motivation. You will gain confidence in yourself. You will not waste your time. Are you ready? So let's go! In this 3-level game, two numbers are presented to you each turn. There are 10 rounds in a game and your time is timed and saved if you have 10/10. You must add these two numbers in an extreme way. You give your answer by pressing one of the 9 digits. The answer is always a number between 1 and 9. At level 1, the two numbers presented are between 1 and 10. (8 + 7) is equal to 6 in the world of Extreme Addition®. Why? Because (8 + 7) = 15, then you separate 15 into (1 + 5) = 6 At level 2, the two numbers presented are between 10 and 99. (28 + 32) is equal to 6 in the world of Extreme Addition®. Why? Because (28 + 32) = 60, then you separate 60 into (6 + 0) = 6 At level 3, the two numbers presented are between 100 and 999. (102 + 108) is equal to 3 in the world of Extreme Addition®. Why? Because (102 + 108) = 210, then you separate 210 into (2 + 1 + 0) = 3 Will you take up the challenge? Mental arithmetic is the daily maintenance of all your mental faculties! Here are some tips to save time in your extreme additions: Tip 1 The result of adding a two-digit number with 9 is quickly obtained from this number as follows: - The number of units minus 1. - The tens digit plus 1. Examples: (25 + 9) = 34 (46 + 9) = 55 (78 + 9) = 87 Tip 2 The result of the extreme addition of 9 with any number from 1 to 9 equals that number. Examples: (4 + 9) => 4 because (4 + 9) = 13 and (1 + 3) = 4 (2 + 9) => 2 because (2 + 9) = 11 and (1 + 1) = 2 (7 + 9) => 7 because (7 + 9) = 16 and (1 + 6) = 7 (9 + 9) => 9 because (9 + 9) = 19 and (1 + 8) = 9 Tip 3 It is faster to add 245 + 637 to the extreme by doing 2 + 4 + 5 + 6 + 3 + 7. Tip 4 Try to get a maximum of 9 in the longest additions, in order to apply tip # 2. Here are all the additions to get the number 9: 1 + 8 = 9 2 + 7 = 9 3 + 6 = 9 4 + 5 = 9 Tip 5 Learn by heart your addition tables, so you no longer have to rely on your fingers to find the result! Lol. 7 + 5 = 12 8 + 4 = 12 6 + 7 = 13 8 + 5 = 13 8 + 6 = 14 7 + 8 = 15 etc ... Be positive, combative, don't give up after a single game, have fun and progress. (This game is available for WatchOS, iOS, MacOS and Apple TV)

Mathji is a math practice app for kids in grades 1-12 that nails the whole loop: generate, correct, and track. • Smart question generation: 200+ topic types from elementary through high school (including AP Calculus and electives), generated on the fly so they never repeat. • Adaptive difficulty: automatically adjusts to your child's performance — steps up when it's too easy, eases off when they get stuck. • Mistake notebook + personalized review: wrong answers are saved automatically and disappear once corrected; future practice prioritizes the topics your child hasn't mastered yet. • Parent dashboard: PIN-protected. See an all-grade learning spectrum, topic mastery, recent sessions, and exactly which questions were missed and what the child picked. • Rewards: kids earn points they can redeem for rewards you define, keeping motivation high. • Five languages: Traditional Chinese, English, Japanese, Korean, and Spanish — for both questions and explanations. Privacy first: all data lives only on your child's device and in your private iCloud (CloudKit); the developer cannot access it. No ads, no in-app purchases, no external links.