Hi there!
Let's use the formula of a sphere and divide it by two (for each hemisphere) to find the volume. Then, we'll create a ratio to figure out how many times larger the larger hemisphere is.
WORK:
Larger hemisphere:
V = 2/3(pi)(8^3)
V = 2/3(512pi)
V = 341.33pi
Smaller hemisphere:
V = 2/3(pi)(4^3)
V = 2/3(64pi)
V = 42.66pi
Ratio:
341.33/42.66
Approximately 4 times
ANSWER:
The larger hemisphere is approximately 4 times bigger than the smaller hemisphere