well i told you that you have to make u signification, i.e get your answer with 3 sig fig..so u got this as your calculation result..3287.5596 but you make it 3287.55, where here there are 6 sig fig.s.
so know i have 2 things to say!
1st: u make a mistake in your rounding!
since 9, 3287.5596, is a number above 5, you have to round the digit before it by adding +1, i.e you get 3287.56..
also let me add u other hints,
if that digit was below 5, u can do what u have done!
while if it 5, you make it in order that digit, i.e. 3287.5596, so if 9 was 5, you have to make the digit before to be even so you get 3287.56
these are the rules in rounding
2nd: i asked you for 3 sig fig right?! so it supposed to be the first 3 digit, i.e 327, 328 or 329
plz now choose one of these concerning for what i said in the 1st, so that i can see that u have understood
Moreover, if u need further helf regarding Sig. Figs, I'm here to help you:)
whish you the best of luck:)