Step-by-step explanation:
given
mass (m) = 315 g
length (l) = 7 cm
width (b) = 3 cm
height (h) = 5 cm
Now
volume (v) = l * b * h
V = 7 * 3 * 5
V = 105 cm³
Density (d) = ?
We know
density is defined as mass per unit volume so
d = m / v
d = 315 / 105
d = 3 g/cm³
Therefore density = 3 g/cm³
Note
If the question is asked to write in SI unit of density then u have to write the unit of density as kg/m³
Hope it will help :)