Which shape has the larger volume? How much larger is it?

The pyramid has the larger volume by three times.

To calculate the volumes:
Pyramid volume = (1/3) * base area * height
= (1/3) * 3 * 5 * 8.41
= 42.05

Prism volume = base area * height
= 3 * 5 * 8.41
= 126.3

The volume of the prism is 126.3 and the volume of the pyramid is 42.05. Therefore, the prism has a larger volume by three times.