posted by Katrina .
when i calculate the density from my measurement,mass=154.4, volume=175.00,and got 0.8823 g/cmexp3 as the answer,so do i have to express the answer in scientific notation or round off it?
No, you do not need to express the answer in scientific notation unless the problem asks for it. Your question about rounding confuses me a little. You have 4 significant figures (sf) in 154.4 and 5 sf in 175.00; therefore, you are allowed 4 significant figures in the answer. I found 154.4/175.00 = 0.8822857. Rounded to 4 sf that will be 0.8823. I hope this helps.