Let the standard quality version downloaded be 'x'
Thus, total size of high quality version downloaded = 2.6*x
Thus, total size of high quality version = 5346 - 2.6x
Now, as per the question, the high quality version downloaded = 4*x
Thus, 4x*4.3 = 5346-2.6x
or, 17.2x = 5346-2.6x