Answer: 890 downloads the high-quality version
Explanation:
Let x be the number of downloads of the high-quality version
1420-x be the number of downloads of the standard version
So, we have the equation
4.5x + 2.7(1420-x) = 5436
4.5x + 3834 - 2.7x = 5436
1.8x + 3834 = 5436
Subtract 3834 on both sides
1.8x = 1602
x = 890