why are some mp3's larger than others?

I downloaded an mp3 today that is:
Size: 17865122 bytes
Header found at: 26624 bytes
Length: 445 seconds
MPEG 1.0 layer 3
320kbit, 17086 frames
44100Hz Joint Stereo
CRCs: No
Copyrighted: No
Original: No

then i have another mp3 a little bit smaller in size but the overall size differance is 10 MB more.. why ?

Size: 7843968 bytes
Header found at: 708 bytes
Length: 392 seconds
MPEG 1.0 layer 3
160kbit, 15025 frames
44100Hz Joint Stereo
CRCs: No
Copyrighted: No
Original: No
Emphasis: None

[fabion]

greetings ttodd

[Quote]
320kbit, 17086 frames

[Quote]
160kbit, 15025 frames

Notice the 320 bitrate and 160 bitrate. That is why the files are different sizes

Normally the higher the bitrate number the better quality and less loss of sound quality.

Check out this link. http://www.gnutellaforums.com/showth...threadid=31710