Multiple choice

The ratio of two numbers is 3 : 4 and their HCF is 5. What is their LCM?

  1. 20

  2. 60

  3. 15

  4. 12

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Numbers are 3x and 4x where x is the HCF. Given HCF=5, numbers are 15 and 20. LCM of 15 and 20 is 60.

AI explanation

Because the highest common factor of the two numbers is 5, we can represent them as 3 times 5 equals 15 and 4 times 5 equals 20. The relationship between highest common factor, least common multiple, and the numbers states that their least common multiple is the product of the numbers divided by their highest common factor. Therefore, the least common multiple is 15 times 20 divided by 5, which equals 60.