There are 2 × 3 = 6 partial products in 123 × 45, because you multiply a 3-digit number by a 2-digit number. The partial products are the following:
100 × 40 = 4000;
100 × 5 = 500;
20 × 40 = 800;
20 × 5 = 100;
3 × 40 = 120; and
3 × 5 = 15.
Read more