# Colored Bead Bars: Inverse Products

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

## Contents

6-9.

### Materials

• Bbox of colored bead bars 1-10
• Chart I

### Presentation

1. The directress asks the child to take the bar of 7, 6 times.
2. The bars are lain in a column.
3. Directress says: "How do we express this?"
4. 7 x 6 = 42 is written down.
5. Now , directress takes the bar of 6, 7 times.
6. These are lain next to the others.
7. When the child writes down 6 x 7 =42, he should observe that the product was the same.
8. Directress says: "Are the multiplication problems the same? Notice that the two rectangles are equal, each having 42. even though the order of the factors is not the same".
9. The child should observe in the written form that the factors are the same, just reversed in their positions.
10. Directress gives several examples of this.

### Purpose

• To help the child on the memorization of multiplication understanding of the commutative property of multiplication.