To find out how many songs Owen downloaded, you can divide the total amount he paid by the price per song.
Owen paid $15 and the price per song is $2.50.
So, the calculation is:
\[ \text{Number of songs} = \frac{\text{Total amount paid}}{\text{Price per song}} = \frac{15}{2.50} = 6 \]
Owen downloaded 6 songs.