The Ultimate AbacusExplore numbers. Discover why.
Learn · explore · explain

Workbook 1 · Numbers and place value

Answer guide

Name: ____________________   Date: ______________

For each activity: predict → explore → explain → check. Draw beads or write place-value labels when useful.

1. Draw or arrange 7 counters. Write its numeral and explain the difference between the quantity and its written symbol.

2. Show zero on a units rod. Why does an empty active area matter?

3. Expand 68 into place values. What does each active bead on the tens rod represent?

4. Read 205. Which rod is empty? Explain why the numeral still has three digits.

5. Show 3.4. Why is a tenths bead different in value from a units bead?

6. Predict 9 + 1. Describe the exchange rather than simply writing 10.

7. Is a larger bead ten times the area of its neighbour? Explain the design limitation.

8. In base four, how many beads are needed per position? What does 13 in base four mean in decimal?

Reflection

What changed your thinking? What question would you ask next?