finding density with significant figures please explain?

Question

A chemist who wished to verify the density of water constructed a cylindrical container of aluminum 4.500 inches high, whose inside radius measured 0.875 inch. The empty cylinder has a mass of 93.054 g. When filled with water, its mass was 270.064 g. Find the density of water from these data, expressing your results in SI units with the correct significant figures.

SCD · Accepted Answer

First find the volume of the cylinder: 
v = pi*(r^2)*h
v = 3.14 * (0.875^2) * 4.500
v = 10.8 in^3

Now convert the cubic inches to cubic centimeters:
(10.8 in^3 / 1) * (2.54 cm / 1 in)^3 = 177 cm^3 = 177 ml

Now find the the mass of the water:
270.064 g - 93.054 g = 177.01 g

Now with the mass and the volume, find the density:
d = m/v
d = 177.01 g / 177 ml
d = 1.000056...

With significant figures, the density of the water is 1.00 g / ml.

finding density with significant figures please explain?

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