As you can see, both blocks have the same depth (5 cm)
So for the first block (left):
[tex]V_1=length*width*depth\\~\\~\\V=8*3*5=120~~cm^3[/tex]
For the second block (right):
[tex]V_2=5*6*2=60~~cm^3[/tex]
Add them up, you get:
[tex]V_{total}=V_1+V_2=120+60=180~~cm^3[/tex]
Done!! :)
