How to use partial products for multi-digit multiplication (grade 4 math)

The partial products algorithm allows anyone (even students who are "bad" at math) to learn how to multiply 2- and 3-digit numbers! It is also easy to see why it works. You don't have to be a math whiz!

Partial products means that we multiply in part-by-part. For example, 7 × 534 is done as 7 × 500, 7 × 30, and 7 × 4, and lastly those parts are added.

This topic is also explained (along with practice problems) in my book Math Mammoth Multiplication 2 – available both as an inexpensive download ($5.10) and as a printed copy.

See also

Remainder in division-related word problems — video lesson

Math Mammoth Multiplication 2 — a workbook with worksheets and lessons for long division, remainder, factors, and primes

Math Mammoth Grade 4 curriculum

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