Please check to see if I'm even doing this right. A cylinder has a volume of 1000 cm^3 ± 2% and a height of 100cm ± 1%. What is the radius of the cylinder? Report your answer with the appropriate percentage error.Here's my work:

volume = [980, 1020]
height = [99, 101]
volume = (pi)r^2 h ⇒ r = √ v / (pi*h)
1.77509052 = √ 980 / (99pi)
1.75742749 = √ 980 / (101pi)
1.81905456 = √ 1020 / (99pi)
1.79293466 = √ 1020 / (101pi)

min{r} = 1.77509052
max{r} = 1.81905456
(max{r} + min{r}) / 2 = 1.79707254
100 * |1.81905456 - 1.79707256)/2= 1.2232

radius = 1.79707254 cm ± 1.2232%
=1.80cm± 1.22% or do a round it up according those confusing rules
2cm ±2 %

Min (r) is

min{r} = 1.75742749

so the average will be slightly lower, around 1.78...

Otherwise it looks ok to me.