To find the Least Common Multiple (LCM) of each pair, I will list the multiples of each number and identify the smallest one they have in common.
1.
30, 4
* Multiples of 30: 30, 60, 90...
* Multiples of 4: 4, 8, 12, ... 56,
60...
* The LCM is 60.
2.
8, 20
* Multiples of 8: 8, 16, 24, 32,
40...
* Multiples of 20: 20,
40...
* The LCM is 40.
3.
10, 5
* Since 10 is a multiple of 5 (5 x 2 = 10), the LCM is just the larger number.
* The LCM is 10.
4.
6, 12
* Since 12 is a multiple of 6 (6 x 2 = 12), the LCM is just the larger number.
* The LCM is 12.
5.
30, 44
* Multiples of 30: 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 360, 390, 420, 450, 480, 510, 540, 570, 600, 630, 660...
* Multiples of 44: 44, 88, 132, 176, 220, 264, 308, 352, 396, 440, 484, 528, 572, 616, 660...
* Alternatively, using prime factorization:
* $30 = 2 \times 3 \times 5$
* $44 = 2^2 \times 11$
* LCM = $2^2 \times 3 \times 5 \times 11 = 4 \times 3 \times 5 \times 11 = 60 \times 11 = 660$.
* The LCM is 660.
6.
8, 6
* Multiples of 8: 8, 16,
24...
* Multiples of 6: 6, 12, 18,
24...
* The LCM is 24.
7.
15, 30
* Since 30 is a multiple of 15 (15 x 2 = 30), the LCM is just the larger number.
* The LCM is 30.
8.
6, 15
* Multiples of 6: 6, 12, 18, 24,
30...
* Multiples of 15: 15,
30...
* The LCM is 30.
Final Answer:
60, 40, 10, 12, 660, 24, 30, 30
Parent Tip: Review the logic above to help your child master the concept of lcm practice worksheet.
