Question

To make a batch of salad dressing, combine 6 tablespoons of oil with 18 tablespoons of vinegar. How many tablespoons of vinegar are needed for every tablespoon of oil?

On the double number line below, fill in the given values, then use multiplication or division to find the missing value:

Answer 1

To find out how many tablespoons of vinegar are needed for every tablespoon of oil, we can set up the ratio based on the given amounts:

You have:
- 6 tablespoons of oil
- 18 tablespoons of vinegar

To find the ratio of vinegar to oil, divide the amount of vinegar by the amount of oil:

\[
\text{Ratio of vinegar to oil} = \frac{18 \text{ tablespoons of vinegar}}{6 \text{ tablespoons of oil}} = 3
\]

This means for every 1 tablespoon of oil, you need 3 tablespoons of vinegar.

So, the answer is that 3 tablespoons of vinegar are needed for every tablespoon of oil.

### Summary:
For the ratio:
- 1 tablespoon of oil : 3 tablespoons of vinegar

Therefore, if you were filling in the values on a double number line:
- On the oil side, you would denote 1, 2, 3, 4, 5, 6 tablespoons.
- On the vinegar side, you would denote 3, 6, 9, 12, 15, 18 tablespoons respectively.