Algebra 101 : Challenge

I don’t understand what’s the point of performing these calculations in an almost unintelligible format.
None of the variables even matter. It’s entirely about the Time/Burnrate, and the Max/Current result autonomously.
If the Time is to 120
And the burnrate is 1, it’s T/1 (120)
And the burnrate is 0.5, it’s just T/0.5 (240)
And 0.25 burnrate? T/0.25 (480)
That’s essentially the maximum fuel. It’s pointless to convolute the equation beyond any basic acquisition of the answer. Time / BurnRate == MaxFuel
Why convolute the equation, I don’t understand C = M - (B * T) or T = C - M/-B

CurrentFuel = MaxFuel - (BurnRate * Time)
Time = CurrentFuel - MaxFuel/-BurnRate
This is nonsensical.

Time/Burnrate == MaxFuel
((Time/MaxTime) * MaxFuel) == aVariable
MaxFuel - AVariable == CurrentFuel

120 / 0.5 == 240 max fuel
It’s currently 49.37218 seconds into flight
(49.37218 / 120) * 240 == aVariable
MaxFuel - aVariable == currentfuel

It’s convoluting the equation and as a result get a more difficult equation with less accuracy
Albeit, I would say doing the equation your way results less computations that improves efficiency.

CurrentFuel == (MaxTime/BurnRate) - ( ((Time/MaxTime) * (MaxTime/BurnRate)) )
now the MaxFuel variable can be entirely omitted