2.70 g/cm^3 converted to kg/m^3

Question

for my answer on my calculator I get 2700 g/m^3     But I’m not sure if I write 270. g/m^3 as my final answer because of the rounding to the least significant figure rule which we started with 2.70 g/cm^3 which is 3 sig figs, so I would think the answer needs the same amount of sig figs hence 270. g/m^3. Do we use the least sig fig rule in this conversion? Why or why not?

Answer 1

Your answer of 2700 g/m³ is correct, but if you present it as 270 g/m3, you are off by a factor of 10, right?  270. is NOT the same as 2700 as it is 1/10th the value.  Look at it as follows:

2.70 g/cm³ x 1 kg/10³ g = 2.70x10^-3 kg/cm³

2.70x10^-3 kg/cm³ x 1cm³/10^-6 m³ = 2.70x10³ kg/m³ (to 3 significant figures)