Which value should be in the numerator? How to think about fractions? **Updated** If I have a word problem with a fraction, how should I know which value should be in the numerator?
Say I have the following problem:
"You stand 180 meters away from a radio tower. One wavelength is 260 meters. How many wavelengths away from the radio tower are you?"
My picture:

I thought of this as an equation which I have to "balance", i.e.
\begin{align}
180x &= 260 \\
x&= \frac{260}{180}= 1.45 \tag 1
\end{align}
... but this was wrong. In the correct answer, the numerator and denominator are flipped, i.e.
\begin{align}
x&= \frac{180}{260}= 0.69 \tag 2
\end{align}
How should I know which value should be in numerator? How should I think?
Update:
Great answers!
My confusion arised beacuse $\frac{180}{260}$ was correct instead of $\frac{260}{180}$.
So suppose the question is instead formulated as:
"You stand 260 meters away from a radio tower. One wavelength is 180 meters. How many wavelengths away from the radio tower are you?"

But in this case I assume
$x=\frac{180}{260}$
is wrong, and the correct answer is instead:
\begin{align}
180x &= 260 \\
x&= \frac{260}{180}= 1.45 \tag 3
\end{align}
I.e. here $\frac{260}{180}$ is correct but in the first formulation $\frac{180}{260}$ was correct. How should I think so I not confuse the numerator/denominator in different cases?

Note the question carefully:

"How many wavelengths away from the radio tower are you?"

Clearly, it wants you to find out the number of wavelengths. Now you may proceed as:
Suppose the number of wavelengths is $x$.
Can you take it up from here?

 Then the length of $x$ wavelengths in all is $260x$. Thus, to cover $180$m, we should have $$260x=180\implies x=\frac{180}{260}=\frac{9}{13}\approx0.69$$

Update: Now for the question which you added later...
Similar logic here also. The length of a wavelength is $180$m. Say the number of wavelengths required to cover $260$m is $y$.
Then think what the total length of all the $y$ wavelengths taken together will be and equate it with your distance from the tower.

 The total length of all the $y$ wavelengths taken together is $180y$.

 Thus, to cover $260$m, the number of wavelengths required will be
 $$180y=260\implies y=\frac{260}{180}=\frac{13}{9}\approx1.44$$

