Record partial products
~7 min
Use the decomposed factors to compute each partial product.
Find Each Partial Product
20 (length)20 (width)
Perimeter = 2 × (20 + 20) = 80
Area = 20 × 20 = 400
To find a partial product, multiply one place-value part from the top factor by one place-value part from the side factor.
💡 Think of it as finding the area of one small box at a time.