1. The problem statement, all variables and given/known data The length and radius of a perfect cylinder are measured with an RMS error of 1%. The RMS error of the inferred volume of the cylinder is.. ? 2. Relevant equations V=∏r2h Hence dV/V=2dr/r+dh/h 3. The attempt at a solution I took dr/r and dh/h as 1%. So got the final answer as 2x1%+1%=3% But the question came with 4 options(one of which is correct): 1.7%, 3.3%, 0.5% and 1% So my answer is wrong ! What am I overlooking ? Is there any special precautions to be taken about RMS error ?