Answer: 260 downloads of the standard version were there.
Step-by-step explanation:
Let x represent the number of downloads of the standard version.
Let y represent the number of downloads of the high-quality version.
Yesterday, the high-quality version downloaded four times as often as the standard version. It means that
y = 4x
The size of the standard version is 2.9 megabytes (MB). the size of the high-quality version is 4.6 MB. the total size downloaded for the two versions was 5538 MB. It means that
2.9x + 4.6y = 5538- - - - - - - - - - - -1
Substituting y = 4x into equation 1, it becomes
2.9x + 4.6 × 4x = 5538
2.9x + 18.4x = 5538
21.3x = 5538
x = 5538/21.3
x = 260
