Explanation

Volume of sphere is given by $v = \frac{4}{3}\pi R^{3}$ Where R is radius of sphere $\therefore\frac{\mathrm{\Delta}V}{V} = 3\frac{\mathrm{\Delta}R}{R}$ Hence, percentage error in volume $\frac{\mathrm{\Delta}V}{V} \times 100 = 3\ \left( \frac{\mathrm{\Delta}R}{R} \times 100 \right)\%$ $= 3 \times 3\% = 9\%$