Two numbers which do not have any factor common other than 1 are called:

Options

A. Rational numbers
B. co-prime numbers
C. prime numbers
D. both (a) and (c)

Answer

**Step-by-Step Solution:**

1. **Understanding the Definition**: We start by defining what is meant by two numbers having no common factors other than 1. This means that the only positive integer that divides both numbers is 1.

2. **Identifying Co-prime Numbers**: Based on the definition, we conclude that two numbers that meet this criterion are referred to as "co-prime numbers."

3. **Example**: To illustrate this, we can take two numbers, for example, 3 and 4.

4. **Finding the Factors**:
- The factors of 3 are: 1, 3
- The factors of 4 are: 1, 2, 4

5. **Checking Common Factors**: Now, we check for common factors between 3 and 4. The only common factor is 1.

6. **Conclusion**: Since the only common factor is 1, we conclude that 3 and 4 are co-prime numbers.

7. **Final Answer**: Therefore, two numbers which do not have any factor common other than 1 are called **co-prime numbers**.

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