Complete the Vertical Calculation

Teaching Notes

Focus: Dividing by Multiples of Ten. Use the worked example and teaching sequence below to explain the reasoning before independent practice.

Before You Begin

• Read the numbers and identify the operation.

Teaching Steps for Parents and Teachers

1. Use multiples of the divisor to find the greatest product no larger than the dividend.
2. Subtract that product from the dividend to find the remainder.
3. Check that the remainder is less than the divisor.
4. Check: divisor × quotient + remainder = dividend.

Worked Examples

165 ÷ 20 = □ R □

1. 20 × 8 = 160 and 20 × 9 = 180, which is greater than 165.
2. 165 − 160 = 5.
3. The remainder 5 is less than 20. Check: 20 × 8 + 5 = 165.

Answer: 8 R 5

Common Mistakes and How to Help

The answer does not match the requested form or place.

Return to the worked example. Ask the learner to explain each step and check the result against the original question.

Questions to Check Understanding

• What does each number in this example represent?
• Why does the final answer have this form?
• Can you explain the same steps using another example?

Practice Advice

Work through the example together. Ask the learner to explain the first two problems, then try three independently. Review the first incorrect step before assigning more practice.

Next Practice

• Use New Numbers to practice the same skill with different values.
• If the learner needs help, return to the example and model each step before trying again.