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A step-by-step multiplication calculator shows long multiplication with carrying, partial products, and column-by-column working — ideal for learning and checking arithmetic.
公式
Multi-digit: (a × 10^m + b) × (c × 10^n + d) = a×c×10^(m+n) + partial products
- a, b, c, d
- Individual digits or groups
- P
- Partial products
ステップバイステップガイド
- 1Multiply each digit of multiplier by each digit of multiplicand
- 2Shift left one position for each digit of the multiplier
- 3Add all partial products to get the final answer
- 4Carry digits when products exceed 9
解いた例
入力
47 × 23
結果
47×3=141; 47×20=940; 141+940=1,081
よくある質問
Why break down multiplication into steps?
Mental math, educational understanding, reduces errors. Shows distributive property of multiplication.
What's the lattice method?
Grid-based multiplication: creates boxes for each digit pair. Older, alternative method (less common today).
How do I multiply 23 × 45?
(20+3) × (40+5) = 20×40 + 20×5 + 3×40 + 3×5 = 800 + 100 + 120 + 15 = 1035.