Here are the solutions for finding the least common multiple (LCM) for each pair of numbers.
1 a. 4, 2
* Multiples of 4: 4, 8, 12...
* Multiples of 2: 2,
4, 6...
* The smallest number they share is 4.
1 b. 3, 9
* Multiples of 3: 3, 6,
9, 12...
* Multiples of 9:
9, 18...
* The smallest number they share is 9.
2 a. 10, 11
* Since 11 is a prime number and doesn't go into 10, you multiply them together.
* $10 \times 11 = 110$
2 b. 4, 6
* Multiples of 4: 4, 8,
12, 16...
* Multiples of 6: 6,
12, 18...
* The smallest number they share is 12.
3 a. 5, 4
* These numbers share no common factors other than 1, so you multiply them.
* $5 \times 4 = 20$
3 b. 6, 3
* Multiples of 6:
6, 12...
* Multiples of 3: 3,
6, 9...
* The smallest number they share is 6.
4 a. 3, 9
* Multiples of 3: 3, 6,
9...
* Multiples of 9:
9...
* The smallest number they share is 9.
4 b. 11, 5
* These are both prime numbers, so you multiply them.
* $11 \times 5 = 55$
5 a. 12, 8
* Multiples of 12: 12,
24, 36...
* Multiples of 8: 8, 16,
24, 32...
* The smallest number they share is 24.
5 b. 7, 4
* These numbers share no common factors, so you multiply them.
* $7 \times 4 = 28$
Final Answer:
1 a. 4
1 b. 9
2 a. 110
2 b. 12
3 a. 20
3 b. 6
4 a. 9
4 b. 55
5 a. 24
5 b. 28
Parent Tip: Review the logic above to help your child master the concept of lcm gcf worksheet.
