A proportion is a statement that two ratios are equal. In this case, we need to determine which option shows equal ratios.
For Option 1: \( \frac{5}{6} = \frac{15}{18} \)
To check if these two fractions are equal, we can simplify \( \frac{15}{18} \):
- The greatest common divisor of 15 and 18 is 3.
- Thus, \( \frac{15}{18} = \frac{15 \div 3}{18 \div 3} = \frac{5}{6} \).
This means: \( \frac{5}{6} = \frac{15}{18} \) is true.
For Option 2: \( \frac{5}{6} = \frac{20}{18} \)
To check if these two fractions are equal, we can simplify \( \frac{20}{18} \):
- The greatest common divisor of 20 and 18 is 2.
- Thus, \( \frac{20}{18} = \frac{20 \div 2}{18 \div 2} = \frac{10}{9} \).
Now we compare: \( \frac{5}{6} \neq \frac{10}{9} \).
Therefore, Option 2 is not a proportion.
The correct answer is: Option 1 is a proportion.