Basic 3 LCM mathematics

1) Find the LCM of 12 and 18:

To find the LCM (Least Common Multiple) of two numbers, we need to find the smallest number that is divisible by both numbers.

Step 1: List the multiples of each number:
Multiples of 12: 12, 24, 36, 48, ...
Multiples of 18: 18, 36, 54, 72, ...

Step 2: Compare the lists and find the smallest number that appears in both lists.
The smallest number that appears in both lists is 36.

Therefore, the LCM of 12 and 18 is 36.

2) Find the LCM of 7 and 9:

Multiples of 7: 7, 14, 21, 28, ...
Multiples of 9: 9, 18, 27, 36, ...

The smallest number that appears in both lists is 63.

Therefore, the LCM of 7 and 9 is 63.

3) Find the LCM of 15 and 25:

Multiples of 15: 15, 30, 45, 60, ...
Multiples of 25: 25, 50, 75, 100, ...

The smallest number that appears in both lists is 75.

Therefore, the LCM of 15 and 25 is 75.