Length of ditch = 5 m
Breadth of ditch = 2.5 m
Height of ditch = 1.5 m
The volume of soil dug out = volume of ditch formed
Since, volume of a cuboid = length × breadth × height
⇒ Volume of ditch = 5 m × 2.5 m × 1.5 m = 18.75 m3
Thus, 18.75 m3 of soil will be taken out.