Mason is mixing up some salad dressing. He takes a bowl that holds 150 ml and fills it 2/3rds with oil and 1/3rd with vinegar. The oil weighs 5 g/ml and the vinegar weighs 4 g/ml. How many grams does the salad dressing weigh?
Thoughts? Step-by-step reasoning:
First find how many ml of oil Mason adds by multiplying the volume of the bowl by the proportion filled with oil: 150 ml * 2 / 3 = 100 ml. Then repeat the process to find how many ml of vinegar he added: 150 ml * 1 / 3 = 50 ml. Now find the weight of the oil by multiplying the volume by the weight / volume ratio: 100 ml * 5 g / ml = 500 g. Do the same procedure with the weight and weight / volume ratio of the vinegar to find its weight: 50 ml * 4 g / ml = 200 g. Now add the weight of the oil and the vinegar to find the weight of the salad dressing: 500 g + 200 g = 700 g.
Thus, the answer is 700.