15 inches is the height of the pyramid
Explanation:
The volume of a cube is a³
Given a = 5 inches
→ Volume = a³
                 = 5³
 = 5×5×5
 = 125 in²
The volume of a pyramid is 
 
 
Given a = 5 inches , h = height of pyramid




then, 





Hence, the height of pyramid is 15 inches