light power action!

[Crappie_Day]

Ok so i have been asking alot of question so her i got a couple more!

Finally I got 4 lights and a battery to run them tell me if I have this right

I have 4x55 watt hallogen bulbs
I have 1 Deep cycle battery that has a 25amp @ 175 Min reserve (which I assume means it runs 25 amp pull for 175 min?!)

So if I have done the math right:
Amp draw=4(lights)x55(watt)/12v :18.33 total pull form 4 lights
25amp/18.33amp=1.36
SO with that being said I sould be getting 175minx1.36 or 238 min out of my 18.33amp system?!?

so with one big deep cycle battery I will only get 4 hrs of power?
If so will it be 100% bright or will it dim at 4hrs or before ?

Im so Confused!!!