Only difficulties with a part of a simple question

hey bud they just divided both sides by "x".... thats everything

Yes .. that's clear. Sorry .. I think my point wasn't.

How to get the idea to do this?
I just saw y = 3x .. is a ratio, so y to x is solveable with this.
Is there a rule for an approach like:
Everytime one sees ratio x to y and an answer mx = ny devide it by either m or n or something like this?

Sorry, it's hard to describe. Sometimes I have a lack of an understanding for some of the steps to take .. or even better: How to get the right ideas.

I guess what I'm lacking of is this sentence:
The ratio of y to x can be expressed as a fraction, so the rephrased question is “what is y / x?”
So .. I first have to state this before I know what to do.
But on the other hand, I was able to figure out the right solution just by looking at the answer.

hey Chris,

its basically just algebra. If you're looking for y/x when you take the first statement (y = 3x) you have to essentially solve for y/x. In order to solve for y/x you need to divide both sides by x. You would end up with y/x=3/1. That's the ratio. The ratio is 3:1 so we know that statement one alone is sufficient. Using the same logic as before, statement 2 alone only gives us y/11 which still doesn't tell us what y is so statement two is insufficient.

I think the key is to look at the equation and think about how to solve for the variable algebraically, but with ratios instead of solving for x or y, you were solving for the ratio; in this case y/x. So you want to manipulate the equation to get y/x on one side of the equation if that is possible then you know just determined the ratio. Hope that was clear and helpful.

Chris8080 wrote: But on the other hand, I was able to figure out the right solution just by looking at the answer.

and that is perfectly fine. dont worry about this, i would have come to the same conclusion as you just by looking at it... the explanations to these problems are for people for whom these things are not obvious.

osirus0830 wrote:Hope that was clear and helpful.

Of course it was.
Thank you very much!

@Svedankae: Ok .. but after having a real bad test result, I want to make sure that my brain gets more mathmatical