Question

Convert $\frac{9}{21}$ to its simplest form.

• A. $\frac{1}{3}$
• B. $\frac{3}{7}$
• C. $\frac{1}{7}$
• D. $\frac{7}{3}$

Answer 1

The correct option is B $\frac{3}{7}$

Let's rewrite the numerator and the denominator into its factors

$\frac{9}{21}=\frac{3\times 3}{3\times 7}=\frac{3}{7}$

The common factors in the numerator and the denominator are canceled
So, the simplest form of $\frac{9}{21}$ is $\frac{3}{7}.$