1. **State the problem:** We are given the fractions of black, silver, and blue cars in a garage as $\frac{1}{12}$, $\frac{7}{12}$, and $\frac{1}{3}$ respectively. We need to write the ratio of black to silver to blue cars in its simplest form. 2. **Write the fractions:** - Black cars: $\frac{1}{12}$ - Silver cars: $\frac{7}{12}$ - Blue cars: $\frac{1}{3}$ 3. **Convert all fractions to have a common denominator:** The denominators are 12 and 3. The least common denominator is 12. - Black: $\frac{1}{12}$ (already with denominator 12) - Silver: $\frac{7}{12}$ (already with denominator 12) - Blue: $\frac{1}{3} = \frac{4}{12}$ 4. **Write the ratio using numerators:** Black : Silver : Blue = $1 : 7 : 4$ 5. **Simplify the ratio if possible:** The numbers 1, 7, and 4 have no common divisor other than 1, so the ratio is already in simplest form. **Final answer:** The ratio of black to silver to blue cars is $1 : 7 : 4$.