This ratio is using different measures (feet and yard), so the first step is converting yard to feet. The conversion rate is:
1 yard = 3 feet.
So we have that:
[tex]\frac{3\text{ feet}}{1\text{ yard}}=\frac{3\text{ feet}}{3\text{ feet}}[/tex]The numerator and denominator of the ratio are the same, so the ratio is equivalent to 1.
[tex]\frac{3\text{ feet}}{3\text{ feet}}=1[/tex]