If a sandwich uses a 3:1 proportion of mayonnaise to mustard, how many ounces of mustard would be needed with 9 ounces of mayonnaise?

To solve the problem, it is important to understand the proportion given, which is 3:1 for mayonnaise to mustard. This means that for every 3 parts of mayonnaise, there is 1 part of mustard.

In this case, if there are 9 ounces of mayonnaise, you can determine how many ounces of mustard are needed based on the established proportion. Since the ratio is 3 parts mayonnaise to 1 part mustard, you can set up a relationship:

1. The total parts in the ratio is 3 (for mayonnaise) + 1 (for mustard) = 4 parts.

2. Each part, in this scenario, corresponds to 9 ounces of mayonnaise divided by 3 parts, which equals 3 ounces per part.

3. Since mustard represents 1 part of the total 4 parts, multiplying the quantity per part (3 ounces) by the number of parts for mustard (1 part) gives you 3 ounces of mustard.

Thus, when you have 9 ounces of mayonnaise, the corresponding amount of mustard needed, following the 3:1 ratio, comes out to be 3 ounces. This confirms that the correct answer is indeed 3 ounces, fulfilling the requirement of the given proportion.