solving a value mixture problem using a linear equation

Question

A Web music store offers two versions of a popular song. The size of the standard version is
2.9
megabytes (MB). The size of the high-quality version is
4.8
MB. Yesterday, the high-quality version was downloaded three times as often as the standard version. The total size downloaded for the two versions was
4844
MB. How many downloads of the standard version were there?

Answer 1

let standard version downloaded x times

then high quality version downloaded 3x times

 

2.9 * x +4.8*3x=4844

 

x=280