# Question #228b4

##### 1 Answer

#### Explanation:

The thing to remember about the **density** of a substance is that it's supposed to tell you the mass of exactly **unit of volume** of that substance.

In your case, the boulder is said to have a density of

You can thus use the density of the boulder as a **conversion factor** to calculate the volume of the

#800 color(red)(cancel(color(black)("g"))) * overbrace(color(blue)("1 cm"^3)/(8color(red)(cancel(color(black)("g")))))^("the given density = 8 g/"color(blue)("cm"^3)) = color(darkgreen)(ul(color(black)("100 cm"^3)))#

The answer is rounded to one **significant figure**.

So remember, when a problem provides you with the **density** of the substance, it's essentially giving you the mass of exactly **unit of volume** of that substance.