howdy! let me just say you guys are programming + maths freaks (in a good way).. i will become one of you one day ;D, u guys are my idols ()

i know this is a programming forum.. but i searched maths forums on google and i ended up here. i am currently yr 10 on my holidays... just studying for yr 11 so i can get ahead of my maths class. Im doing great in everything except LINEAR EQUATIONS.

if you could help me that would be great, if ur here to flame me then get it over and done with.. i'm just having problems with this question below, i got the answer.. but i'm not sure if the formula is right

Two tanks contain equal amounts of water. They are connected by a pipe and 3000 litres of water is pumped from one tank to the other. One tank then contains 6 times as much water as the other. How many litres of water did each tank contain originally?

correct me if im wrong(which i know i am) but i got this formula>

t - 3000 = t - 3000 * 6

i know the answer is t = 4200
but i know my formula isnt right because i had to guess my answer.

thanks in advanced!!

-joseph