im new to chemistry and i dont understand at all. how are the 4&7 in 0.4790 the only significant numbers?

Rules of Significant Figures with Multiplication/Division \& Addition/Subtraction Calculations involving both multiplication/division AND addition/subtraction: -Follow order of operations. - Keep track of significant figures through each step and only round at the end. Ex:6.785.903(5.4895.01)=6.785.9030.4790=19.170719 Since the first operation is subtraction, only the 4 and 7 are significant in 0.4790, so we keep track by underlining those digits. Because we multiplied in the second operation, we want our final 5.903 has 4 sig figs. least number of sig. figs. 6.78 has 3 sig. figs., 5.903 has 4 sig. figs., and 0.4790 has only 2 sig. figs. Because of the sig. figs