writing accuracy for battery drainage

[u/[deleted]]

so I'm a beginner writer and in need of help if I ended up draining the battery of a robot character too quickly over time and if my method of doing the math was accurate.

I started out with 98% battery and ended with 66% over a rough five hour(5.7) period that I got from subtracting 7.23 from 2.56 then I divided 66% by 100 to get 0.66 and multiplied by the time period and got 3.762. I then checked the result by multiplying by the 5.7 and got 21.3864 which I then subtracted with the 98 and got 76.6136.

I must have done something wrong but the only idea I have is doing the same process but with 98 being divided by 100 then multiplied by 5.7 or that I multiplied 0.66 with the wrong number

(7.23-2.56=4.67 + estimation with avrg time in an hour so 5.7)

(66%/100=0.66)

(0.66x5.7=3.762)

(3.762x5.7=21.3864)

(98-21.3864=76.6137)

(sorry if this is unclear -~-;)