A mechanic used 49 quarts of oil in 7 cars. At this rate, how much oil would he use to change the oil in 17 cars?

Each car used 7 quarts of oil. So 7 cars would use 7×17 quarts which would be 119 quarts.

i think there was a typo. you wrote pat brings 3 quarts of ice-cream to the party. each serving of ice-cream is 1 6 quart. how many total servings of ice-cream does pat bring to the party? i think the bold is supposed to be 1/6. so 1 quart of ice cream = 6 servings. 6 * 3 = 18.