Answer: If Miss Reed combines one fluid ounce of oil with three fluid ounces of vinegar, she gets a total of four fluid ounces of salad dressing. Therefore, the ratio of oil to total dressing is 1:4, and the ratio of vinegar to total dressing is 3:4.
If Miss Reed wants to make a larger amount of salad dressing using the same ratio of oil to vinegar, she can simply scale up the quantities while maintaining the same ratio. For example, if she wants to make 12 fluid ounces of salad dressing, she would need:
- 3 fluid ounces of oil (since the ratio of oil to total dressing is 1:4)
- 9 fluid ounces of vinegar (since the ratio of vinegar to total dressing is 3:4)
She can combine these quantities to get a total of 12 fluid ounces of salad dressing, with the same oil-to-vinegar ratio as before.