Aweb music store offers two versions of a popular song. the size of the standard version is 2.5 megabytes (mb). the size of the high-quality version is 4.7 mb. yesterday, there were 780 downloads of the song, for a total download size of 3006 mb. how many downloads of the standard version were there?

There were 300 standard version of songs downloaded at Web music store.

Step-by-step explanation:

Let the number of standard version of song download be 'x'.

Let the number of high-quality version of song download be 'y'.

Given:

Total songs downloaded = 780

Now we know that;

Total songs downloaded is equal to sum of the number of standard version of song download and the number of high-quality version of song download.

framing in equation form we get;

Also Given:

Size of standard version of song = 2.5 MB

Size of high-quality version of song = 4.7 MB

Total Download size = 3006 MB

Now we know that;

Total Download size is equal to sum of Size of standard version of song multiplied by the number of standard version of song download and Size of high-quality version of song multiplied by the number of high-quality version of song download.

framing in equation form we get;

Now Multiplying equation 1 by 2.5 we get;

Now Subtracting equation 3 from equation 2 we get;

Substituting the value of y in equation 1 we get;

Hence there were 300 standard version of songs downloaded at Web music store.

(n^3 - n)

= n(n-1)(n+1)

since it is divisible by 3 and 2 ,because it is a multiple 3 consecutive number

if, n-1 is odd then n+1 is also odd, then it is a multiple of 9

but if, n-1 is even then n+1 is also even, then it is a multiple of 4

so, largest multiple = max(9*2, 4*3) = max(18, 12) = 18