A web music store offers two version of a popular song. the size of the standard version is 2.9 megabytes (MB). the size of the high-quality version is 4.6 MB. yesterday, the high-quality version downloaded four times as often as the standard version. the total size downloaded for the two versions was 5538 MB. how many downloads of the standard version were there?

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

47 - 90 = 43

43 - 180 = x

x = 137