- #1

shuxue

- 7

- 0

Volume of the beach = N X Volume of each grain

N = (Volume of the beach) / (Volume of each grain)

[tex]N=\frac{(500)(100)(3)}{(\frac{4}{3}\pi)(0.5\times10^{-3})^3}=2.9\times10^{14}\approx3\times10^{14}[/tex]

Why equal sign is used between [tex]\frac{(500)(100)(3)}{(\frac{4}{3}\pi)(0.5\times10^{-3})^3}[/tex] and [tex]2.9\times10^{14}[/tex] instead of approximation sign? Why approximation sign is used between [tex]2.9\times10^{14}[/tex] and [tex]3\times10^{14}[/tex] instead of equal sign?