An analytical chemist uses thin-layer chromatography (TLC) to isolate and identify pigments extracted from spinach leaves.
One of the separated components, lutein, is found to have a retention factor (RfR_{\text{f}}Rf) value of 0.45. On the developed TLC plate, the center of the yellow spot corresponding to lutein is measured to be 5.4 cm from the start line.
Calculate the distance, in centimeters, traveled by the solvent front from the start line.