Is there a way for me to download MP3-formatted files onto my IPad Mini (1st generation) (16gb)?

Is there a way for me to download the newest IOS 8 update onto my IPad Mini without taking up 7gb? I really need to know. I've deleted all of my apps except about 3 or 4, but I still don't have enough storage space to download it. the apps I have left have a total of about 0.5gb. My Ipad Mini is supposed to be a 16gb, so I don't understand why it won't let me update.