What is the greatest factor 10 and 20 have in common?

The greatest factor that 10 and 20 share is known as the greatest common divisor (GCD). In this case, the GCD of 10 and 20 is 10.

Understanding Factors

Factors are numbers that can be multiplied together to get another number. For example:

• Factors of 10: 1, 2, 5, 10
• Factors of 20: 1, 2, 4, 5, 10, 20

Finding the GCD

To find the GCD, we look for the largest number that appears in both lists of factors. Here, 10 is the highest number that divides both 10 and 20 without leaving a remainder.

Why It Matters

Knowing the GCD is useful in various mathematical applications, such as simplifying fractions or solving problems involving ratios.