Mr. Holms used \( \frac{4}{5} \) of a carton of orange juice. He used equal amounts of the leftover juice for 2 servings. What fraction of the whole carton of juice did he use for each serving?

After Mr. Holms used \( \frac{4}{5} \) of a carton of orange juice, he had \( 1 - \frac{4}{5} = \frac{1}{5} \) of the carton left. He divided the leftover juice equally for 2 servings, so the amount used for each serving is \( \frac{1}{5} \div 2 = \frac{1}{10} \). Therefore, for each serving, Mr. Holms used \( \frac{1}{10} \) of the whole carton of orange juice.