Which of the following pairs of numbers has an HCF of 1? (2023)
Practice Questions
Q1
Which of the following pairs of numbers has an HCF of 1? (2023)
8 and 12
15 and 28
9 and 27
14 and 21
Questions & Step-by-Step Solutions
Which of the following pairs of numbers has an HCF of 1? (2023)
Step 1: Understand what HCF means. HCF stands for Highest Common Factor, which is the largest number that divides two or more numbers without leaving a remainder.
Step 2: Identify the two numbers you want to check. In this case, the numbers are 15 and 28.
Step 3: List the factors of each number. The factors of 15 are 1, 3, 5, and 15. The factors of 28 are 1, 2, 4, 7, 14, and 28.
Step 4: Find the common factors between the two lists. The only common factor of 15 and 28 is 1.
Step 5: Determine the HCF. Since the highest common factor is 1, it means that 15 and 28 have no other common factors.
Step 6: Conclude that since the HCF is 1, the numbers 15 and 28 are coprime, meaning they do not share any factors other than 1.
