How do I do this math question? Pre-calc :c

It's kinda hard to type out so I took a picture from the textbook, I hope it's easy to read.
http://i46.tinypic.com/308h0gj.jpg

V1/V2=T1/T2
V1=T1/T2xV2
V1=[(n-1)/3]/[(n+4)/6] x (n^2-16)/(n-1)

V1=2n-8

plus: point this n^2-16=(n+4)(n-4)

2n-8 but that's just a guess without a pencil.

Just sub the numbers into V2 times the quantity T1 / T2

Yup, I had to correct it to minus. Not bad for someone who graduated high school 32 years ago!

What in particular are you having problems with? (How far have you got?)