For this question, you need to find the volume of the whole pyramid (frustum + small pyramid)
For whole pyramid:
V=1/3 x (lwh)
V=1/3 x (22x11x33) -> 33 is from 24+9
V=2662cm^3
For small pyramid:
V=1/3 x (6x3x9)
V=54cm^3
Now, volume of frustum = 2662-54= 2608cm^3
I hope this is correct and explained ok