Passage from One Square to a non-Succeeding Square
From wikisori
Contents
Age
6-9.
Materials
- Box of colored bead bars 1-10
- One each of the squares of 1-10
- Rubber bands
Preparation
Presentation
- The directress volunteers to assist in constructing a square of 9 from a square of 5.
- Directress says: "What is the difference when you take 5 from 9? "
- So, how many more bars of 5 must be added to this side to make 9?"
- Four bars of 5 are added to the right side.
- In the same way 4 5-bars are added to the bottom.
- Again, there is a hole.
- Count the number of beads on the sides of the hole...4 by 4.
- Four 4-bars can be replaced by the square,
- Use the square of 9 to control:
- 5 x 5 + 5 x 4 + 5 x 4 + 4 x 4
- What was added? 25 + 20 + 20 + + 16 = 81
- 9 x 9 = 81
Control Of Error
Points Of Interest
Purpose
Variation
Links
Handouts/Attachments