Answer:
Both boxes have the same amount of empty space
Explanation:
Given
Cube Box

Robert:
1 glass marble

Susan:
1000 glass marble

Required
Whose box has more empty space?
First, we need to calculate the volume of the cubic box.

Substitute 10cm for Length


Next, calculate the volume of Robert's glass
Volume is calculated as:
---- Volume of a sphere
Where
r = radius

--- Given
Substitute 10 for diameter


So:




Next, we determine the volume of Susan's 1000 glasses
Volume is calculated as:
---- Volume of a sphere
Where
r = radius

--- Given
Substitute 1cm for diameter


Substitute 0.5cm for radius in 



But there are 1000 glasses.
So, the volume of 1000 glasses is:


--------------------------------------------------------------------------------------------------------------
For Robert:

For Susan:

Since, they have the same volume.
Both boxes have the same amount of empty space