A common multiple is a number that is a multiple of two or more other numbers.
A common multiple is a number that results from the multiplication of two whole numbers larger than 1.
To find the common multiple of two numbers, first write the multiples of both the numbers and then choose all the common multiples.
The smallest common multiple of two numbers is called least common multiple or lowest common multiple (LCM).
Multiples of 6 are 6, 12, 18, 24, 30, 36, 42, 48,...
Multiples of 8 are 8, 16, 24, 32, 40, 48,...
So, the common multiples of 6 and 8 are 24, 48.
A. 10, 25, 30, 45
B. 15, 25, 35, 45
C. 10, 20, 30, 40
D. 5, 10, 15, 20
Correct Answer: C
Step 1: The multiples of 5 are 5, 10, 15, 20, 25,...
Step 2: The multiples of 10 are 10, 20, 30, 40, 50,...
Step 3: We observe that all the multiples of 10 are also the multiples of 5.
Step 4: Therefore, 10, 20, 30, 40 are the common multiples of 5 and 10.