Considering why the number, 673241.0, is given instead of 673241, we assume the digit at tenth place,0, is significant for some reasons. Thus, the given number has 7 significant figures: 6,7,3,2,4,1,and 0.*
Therfore, the scientific notation for 673241.0 is 6.734210 x 10^5.
* If the number of significant figure is 4, the number is rounded to the nearest hundred. Thus, the scientfic notation for the given number is 6.732 x 10^5