Answer: There were 290 downloads of the high-quality version.
Explanation:
 Let be "s" the number of downloads of the standard version and "h" the number of downloads of the high-quality version.
 Set up a system of equations:
 

 You can use the Elimination method. Multiply the first equation by -2.1, add the equations and then solve for "h":
 

 Therefore, there were 290 downloads of the high-quality version.