Multiplication

Detailed description

1. A rectangular prism made of blocks. Dimensions 5 × 3 × 1. Underneath this diagram 5 × 3 = 3 × 5.
2. A rectangular prism made of blocks. Dimensions 5 × 3 × 2. Underneath this diagram (5 × 3) × 2 = (3 × 5) × 2.