【良問】最後まで気持ちいい覆面算【智辯和歌山中 2003 虫食い算】

#ChibenWakayamaJuniorHighSchool #2003 #Cryptarithmetic #IncompleteNumberPuzzle #JuniorHighSchoolEntranceExam ■ Problem Chiben Wakayama Junior High School 2003 A0B +AAB +ABB ──── 2CCA Find the integers that fit in A, B, and C. ■ Strategy Start from the units digit of the long division. ■ Units Digit B + B + B = A Therefore, The units digit of 3B is A. Let the carry-over be d. ■ Tens Digit 0 + A + B + d = C ■ Hundreds Digit A + A + A + Carry-over = C Therefore, 3A + e = C However, since the result is 2CCA, The thousands digit is 2. ■ Thousands Place 3A + e is between 20 and 30 (inclusive). ■ Determine A Since 3A is 20 or greater, A = 7, 8, or 9. ■ Check the Units Place A is the units digit of 3B. Check B. B=3 → 3B=9 → A=9 Try this first. ■ Verification Units place carry-over d=0 Tens Place 0+9+3=12 → C=2, carry-over e=1 Hundreds Place 9+9+9+1=28 → C=8 They don't match. ■ Next B=6 → 18 → A=8 d=1 Tens digit 0+8+6+1=15 → C=5 e=1 Hundreds digit 8+8+8+1=25 → C=5 Match! ■ Verification 806 +886 +866 ──── 2558 Valid. ■ Conclusion A=8 B=6 C=5 ■ Points ・Start from the ones digit ・Track the carry-over ・Narrow down the conditions and try them A beautiful cryptarithmetic problem that tests logical thinking, typical of Chiben Wakayama. 🔗 Related Videos & Recommended Links [Junior High School Entrance Exam: Math Calculation Problem Explanation Series] ▶    • 灘中入試問題 2005年度1日目｜素因数分解で分数の計算問題   [Junior High School Entrance Exam: Practice Problems on the Properties of Integers] ▶    • 【魔方陣の攻略法】真ん中の数の見つけ方！公務員試験＆中学受験の数的処理対策｜算数過去...   [Kaisei Junior High School Entrance Exam Problems & Past Paper Explanation Series] ▶    • 【開成中学の算数】単位分数の和と整数問題を徹底解説！2010年度過去問に挑戦｜中学受験算数   [Nada Junior High School Entrance Exam Problems & Past Paper Explanation Series] ▶    • 灘中入試問題 2005年度1日目｜素因数分解で分数の計算問題   📢 A Request to Viewers If you found this video helpful, please let us know by liking or commenting! We also welcome requests for explanations of other problems! 📌 About This Channel This channel provides methods for steadily improving the skills necessary for entrance exams while learning arithmetic and mathematics in a fun way. We fully support everyone who wants to "train their thinking skills" and "overcome their weaknesses"! 📩 Business Inquiries/Contact For interview and business inquiries, please contact us here: 📧 [email protected] #JuniorHighSchoolEntranceExam #EntranceExamArithmetic #Mathematics