Comparing ratios?

Question

Im 12 and in need help on how to do these comparing stuff.

Here is my problem/question

So how do I figure this out?

Answer 1

I guess they want you to say, if the purple colour needs 5 parts of blue paint to 2 parts of red paint, then: (a) how many parts of red paint would you need to mix with 15 parts of blue paint; and (b) how many parts of blue paint would you need to mix with 14 parts of red paint, to make the same purple colour?

Well, if so, then for (a), you could make 15 parts of blue by taking 5, and 5, and 5 parts of blue again; so, if you take 2 of red for each 5 of blue, then how many parts of red would you have used?

Similarly, you could make 14 parts of red by taking 2 parts of red, over and over again - how many times? - and if you then mix in 5 parts of blue, over and over again, the same number of times, then how many parts of blue would you have used altogether?