Division of Numbers – Basic 3 Mathematics Lesson Note (Second Term)

A. counting skill: numbers 831-850

Counting from 831 to 850: 831, 832, 833, 834, 835, 836, 837, 838, 839, 840, 841, 842, 843, 844, 845, 846, 847, 848, 849, 850

Practice counting:

• From 835 to 845: _______
• From 842 to 850: _______
• Backwards from 850 to 840: _______

Skip counting by 10s: 830, 840, 850

Fill in missing numbers:

• 836, 837, _____, 839, _____
• 845, _____, 847, _____, 849
• _____, 832, _____, 834, _____

B. writing skill: writing of the numbers

Write in words:

• 831 = Eight hundred and thirty-one
• 835 = Eight hundred and thirty-five
• 840 = Eight hundred and forty
• 845 = Eight hundred and forty-five
• 850 = Eight hundred and fifty

Write in figures:

• Eight hundred and thirty-three = _______
• Eight hundred and thirty-eight = _______
• Eight hundred and forty-two = _______
• Eight hundred and forty-seven = _______
• Eight hundred and forty-nine = _______

Practice:

• 834 = _______
• 841 = _______
• Eight hundred and thirty-six = _______
• Eight hundred and forty-eight = _______

C. division without remainder

What is division? Division is sharing equally or finding how many groups we can make.

Division facts:

• 8 ÷ 2 = 4 (8 shared between 2 groups gives 4 each)
• 12 ÷ 3 = 4 (12 shared between 3 groups gives 4 each)
• 15 ÷ 5 = 3 (15 shared between 5 groups gives 3 each)

Basic division practice:

1. 6 ÷ 2 = _____
2. 9 ÷ 3 = _____
3. 10 ÷ 5 = _____
4. 12 ÷ 4 = _____
5. 14 ÷ 2 = _____
6. 18 ÷ 6 = _____
7. 20 ÷ 4 = _____
8. 16 ÷ 8 = _____

Division and multiplication relationship: If 4 × 3 = 12, then 12 ÷ 3 = 4 and 12 ÷ 4 = 3

Practice using multiplication facts:

1. 5 × 4 = 20, so 20 ÷ 5 = _____ and 20 ÷ 4 = _____
2. 6 × 3 = 18, so 18 ÷ 6 = _____ and 18 ÷ 3 = _____
3. 7 × 2 = 14, so 14 ÷ 7 = _____ and 14 ÷ 2 = _____

D. factors of whole numbers not exceeding 48

What are factors? Factors are numbers that divide exactly into another number.

Finding factors: To find factors of a number, find all numbers that divide it without remainder.

Examples: Factors of 12:

• 12 ÷ 1 = 12 ✓
• 12 ÷ 2 = 6 ✓
• 12 ÷ 3 = 4 ✓
• 12 ÷ 4 = 3 ✓
• 12 ÷ 6 = 2 ✓
• 12 ÷ 12 = 1 ✓ Factors of 12: 1, 2, 3, 4, 6, 12

Factors of 16:

• 16 ÷ 1 = 16 ✓
• 16 ÷ 2 = 8 ✓
• 16 ÷ 4 = 4 ✓
• 16 ÷ 8 = 2 ✓
• 16 ÷ 16 = 1 ✓ Factors of 16: 1, 2, 4, 8, 16

Practice finding factors:

1. Factors of 8: 1, 2, 4, _____
2. Factors of 15: 1, 3, 5, _____
3. Factors of 18: 1, 2, 3, 6, 9, _____
4. Factors of 20: 1, 2, 4, 5, 10, _____
5. Factors of 24: 1, 2, 3, 4, 6, 8, 12, _____

Complete the factor lists:

1. Factors of 6: _______
2. Factors of 9: _______
3. Factors of 10: _______
4. Factors of 14: _______
5. Factors of 21: _______

E. quantitative reasoning

Word problems:

1. 24 sweets are shared equally among 6 children. How many sweets does each child get?
2. A farmer has 36 eggs. He packs them in boxes of 4. How many boxes does he need?
3. 30 pupils are arranged in equal rows of 5. How many rows are there?
4. Kemi has 42 marbles. She gives them equally to 7 friends. How many marbles does each friend get?

Factor problems:

1. Which numbers divide 12 exactly? _______
2. List all factors of 18: _______
3. What are the factors of 30? _______

Number relationships:

1. If 8 × 6 = 48, then 48 ÷ 8 = _____ and 48 ÷ 6 = _____
2. If 7 × 4 = 28, then 28 ÷ 7 = _____ and 28 ÷ 4 = _____

Pattern recognition:

1. 2, 4, 6, 8, 10, 12 are all factors of _____
2. 1, 3, 9 are factors of _____
3. 1, 2, 4, 8 are factors of _____

Missing numbers:

1. 36 ÷ _____ = 9
2. _____ ÷ 5 = 7
3. 45 ÷ _____ = 5

CLASS EXERCISES

1. Count from 838 to 848:
2. Write in words:
   1. 837 = _______
   2. 843 = _______
   3. 850 = _______
3. Write in figures:
   1. Eight hundred and thirty-nine = _______
   2. Eight hundred and forty-six = _______
4. Divide without remainder:
   1. 8 ÷ 2 = _____
   2. 15 ÷ 3 = _____
   3. 24 ÷ 6 = _____
   4. 28 ÷ 4 = _____
5. Find all factors:
   1. Factors of 12: _______
   2. Factors of 18: _______
   3. Factors of 20: _______
6. Use multiplication to help with division:
   1. 6 × 4 = 24, so 24 ÷ 6 = _____ and 24 ÷ 4 = _____
   2. 5 × 8 = 40, so 40 ÷ 5 = _____ and 40 ÷ 8 = _____
7. Word problems:
   1. 32 books are arranged in 8 equal piles. How many books are in each pile?
   2. 45 oranges are packed in bags of 9. How many bags are needed?
8. Complete the factor lists:
   1. Factors of 16: 1, 2, 4, 8, _____
   2. Factors of 21: 1, 3, 7, _____
9. Find the missing numbers:
   1. 42 ÷ _____ = 6
   2. _____ ÷ 8 = 5
10. Problem solving: A teacher has 48 stickers. She wants to give them equally to her pupils. What are all the possible ways she can divide them? (List the factors of 48)