The least common multiple is the product of all factors in the greatest number of their occurrence. The least common multiple of 2, 7 and 28 is 28.

Answer: LCM of 7 and 14 is 14.

42

63

Answer: LCM of 2, 3, and 7 is 42 The least common multiple of 2, 3, and 7 is the smallest number among all common multiples of the numbers, 2, 3, and 7.

The least common multiple of 25, 50 and 100 is 100.

100

What is the LCM of 25 and 25? The LCM of 25 and 25 is 25.

LCM of 25 and 50 is 50.

12

Final Step: Biggest Common Factor Number The biggest common factor number is the GCF number. So the greatest common factor 20 and 30 is 10.

Final Step: Biggest Common Factor Number The biggest common factor number is the GCF number. So the greatest common factor 12 and 24 is 12.

Factors of 12 = 1, 2, 3, 4, 6 and 12. Factors of 18 = 1, 2, 3, 6, 9 and 18. Therefore, common factor of 12 and 18 = 1, 2, 3 and 6. Highest common factor (H.C.F) of 12 and 18 = 6 [since 6 is the highest common factor].

HCF Example 1 and 3 are the only common factors (numbers which are factors of both 12 and 15). Therefore, the highest common factor of 12 and 15 is 3.

A number can have lots of factors. 20 also has 1, 2 and 10 as factors because 1 x 20 and 2 x 10 also equal 20. The highest common factor of two numbers is the largest whole number which is a factor of both. This can sometimes also be called the Greatest Common Factor (GCF).

3

Final Step: Biggest Common Factor Number The biggest common factor number is the GCF number. So the greatest common factor 7 and 21 is 7.

1