Singapore Math Level 2A & 2B – Unit 6: MULTIPLYING AND DIVIDING NUMBERS BY 4 – 5 – AND 10
Examples:
- There are 10 SUVs in a parking lot.
Each SUV has 4 wheels.
How many wheels are there altogether?
10 × 4 = 40
There are 40 wheels altogether.
- Uncle Ron works 5 days each week.
How many days does he work in 8 weeks?
8 × 5 = 40
He works 40 days in 8 weeks.
- There are 80 pens.
Andre ties 10 pens in each bundle.
How many bundles of pens does Andre tie?
80 ÷ 10 = 8
Andre ties 8 bundles of pens.
Complete the following tables.
- Each car has 4 wheels.
| Number of cars | 1 | 2 | 4 | 9 | |
| Number of wheels | 4 | 8 | 28 |
Solution:
| Number of cars | 1 | 2 | 4 | 7 | 9 |
| Number of wheels | 4 | 8 | 16 | 28 | 36 |
[Note: Multiplying and Dividing Numbers by 4; then, 4×4=16, 28÷4=7, 9×4=36.]
- Each hand has 5 fingers.
| Number of hands | 2 | 6 | 10 | ||
| Number of fingers | 10 | 20 | 45 |
Solution:
| Number of hands | 2 | 4 | 6 | 9 | 10 |
| Number of fingers | 10 | 20 | 30 | 45 | 50 |
[Note: Multiplying and Dividing Numbers by 5; then, 20÷5=4, 6×5=30, 45÷5=9, 10×5=50.]
- Each vase has 10 flowers.
| Number of vases | 3 | 7 | 8 | ||
| Number of flowers | 30 | 50 | 100 |
Solution:
| Number of vases | 3 | 5 | 7 | 8 | 10 |
| Number of flowers | 30 | 50 | 70 | 80 | 100 |
[Note: Multiplying and Dividing Numbers by 10; then, 50÷10=5, 7×10=70, 8×10=80, 100÷10=10.]
Fill in each blank with the correct answer.
- 6×4=___
- 3×5=___
- 6×5=___
- 9×5=___
- 3×10 =___
- 8×10 =___
- 9×4 =___
- 7×10 =___
- 2×4 =___
- 7×5=___
Solution:
- 6×4=24
- 3×5=15
- 6×5=30
- 9×5=45
- 3×10 =30
- 8×10 =80
- 9×4 =36
- 7×10 =70
- 2×4 =8
- 7×5=35
Fill in each blank with the correct answer.
- 30÷5=___
- 20÷10=___
- 16÷4=___
- 40÷5=___
- 24÷4=___
- 90÷10=___
- 12÷4=___
- 100÷10=___
- 10÷5=___
- 40÷10=___
Solution:
- 30÷5=6
- 20÷10=2
- 16÷4=4
- 40÷5=8
- 24÷4=6
- 90÷10=9
- 12÷4=3
- 100÷10=10
- 10÷5=2
- 40÷10=4
Write 2 multiplication & also 2 division sentences for each set of pictures.
24.
___×___=___ ___÷___=___
___×___=___ ___÷___=___
Solution:
5 × 4 = 20
4 × 5 = 20
20 ÷ 5 = 4
20 ÷ 4 = 5
25.
____×___=___ ____÷___=___
____×___=___ ____÷___=___
Solution:
6 × 4 = 24
4 × 6 = 24
24 ÷ 6 = 4
24 ÷ 4 = 6
26.
___×____=___ ___÷____=___
___×____=___ ___÷____=___
Solution:
7 × 10 = 70
10 × 7 = 70
70 ÷ 7 = 10
70 ÷ 10 = 7
27.
____×____=___ ___÷____=___
____×____=___ ___÷____=___
Solution:
8 × 5 = 40
5 × 8 = 40
40 ÷ 8 = 5
40 ÷ 5 = 8
28.
___×____=___ ___÷____=____
___×____=___ ___÷____=____
Solution:
3 × 4 = 12
4 × 3 = 12
12 ÷ 3 = 4
12 ÷ 4 = 3
Solve the following story problems. Show your work in the space below.
- Mom buys 6 bags of apples. There are 5 apples in each bag. How many apples are there altogether?
There are ___ apples altogether.
Solution:
6 × 5 = 30
There are 30 apples altogether.
- Sam spends $10 every week. How much does he spend in 8 weeks?
Sam spends $ ___ in 8 weeks.
Solution:
8 × $10 = $80
Sam spends $80 in 8 weeks.
- Leyla bought 4 meters of fabric. Each meter cost $7. How much did Leyla spend altogether?
Leyla spent $___ altogether.
Solution:
4 × $7 = $28
Leyla spent $28 altogether.
- Dad sews 15 buttons on 3 shirts. How many buttons are there on each shirt?
There are ___ buttons on each shirt.
Solution:
15 ÷ 3 = 5
There are 5 buttons on each shirt.
- Alfred packs 10 packages of crackers into each bag. If there are 1 hundred packages of crackers, how many bags does Alfred need?
Alicia needs ___ bags.
Solution:
100 ÷ 10 = 10
Alicia needs 10 bags.
- Maggy saves $5 every month. How much will she save in 10 months?
Maggy will save $___ in 10 months.
Solution:
10 × $5 = $50
Maggy will save $50 in 10 months.
