what is 18/21 in its simplest form

Divide the numerator and denominator by 3. What do you get?

6/7

To simplify the fraction 18/21, you need to find the greatest common divisor (GCD) of the numerator (18) and the denominator (21), and then divide both the numerator and denominator by this GCD.

Step 1: Find the GCD of 18 and 21.
To find the GCD, you can use various methods such as prime factorization, listing multiples, or using a GCD calculator. In this example, let's use prime factorization.

Prime factorization of 18:
18 = 2 * 3 * 3

Prime factorization of 21:
21 = 3 * 7

The GCD is the product of the common prime factors raised to the lowest powers:
GCD(18, 21) = 3

Step 2: Divide both the numerator and denominator by the GCD (which is 3).

18 ÷ 3 = 6
21 ÷ 3 = 7

Therefore, the simplified form of 18/21 is 6/7.