Salina was at a party and she noticed that the room had 54 balloons. for every red balloon there were 2 yellow balloons and 3 blue balloons. how many blue balloons were there?

This has to do with ratios, so put them into ratios.
1:2:3
After that we add them together and that equals 6,  54 divided by 6  is 9, which is the 1 in the ratio. then we do 9 × 3 which equals 27.
You have the number of blue balloons now.

First, let's put the information about the balloons into a ratio, which would be 1:2:3. We can then add the ratio up, to equal 6. We can then divide 54 by 6, which your answer is 9. Now, let's multiply 9 × 3 to get your answer, 27.

There is 27 blue balloons out of the 54 total.