Question

A Web music store offers two versions of a popular song. The size of the standard version is 2.9megabytes (MB). The size of the high-quality version is 4.1 MB. Yesterday, there were 740 downloads of the song, for a total download size of 2410 MB. How many downloads of the high-quality version were there?

Answer 1

high-quality version downloaded is 220

Explanation:

let s = standard version and

h = high quality version

s + h = 740 equation1

2.9s + 4.1h = 2410 equation2

multiply equation1 by -2.9

-2.9(s + h = 740)

-2.9s - 2.9h = - 2146 equation3

add equations 2 & 3

2.9s + 4.1h = 2410

-2.9s - 2.9h = - 2146

_________________

1.2h = 264

h = 220