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Explanation:
m = mass
v = volume
d = density
The formula we use is
d = m/v
Multiplying both sides by v allows us to solve for m
d = m/v
d*v = m
m = d*v
Now plug in the given density (d = 4) and the given volume (v = 15) and simplify:
m = d*v
m = 4*15
m = 60 grams
Note how,
d = m/v
d = 60/15
d = 4
which helps confirm our answer
