10 longs placed side by side, form a flat (with dimensions 10×10)
10 flats, placed on top of each other form a large cube, with dimensions 10×10×10 = 1000 cubes. -------------------------------------------------------------------------------------------------
each small cube (unit cube) represents the number 1.
thus each long represents 10 each flat represents 100
and each large cube represents 1,000
The number 13,450 can be written as
1*10,000+3*1000+4*100+5*10 using the expanded form.
This means that there are 13 large cubes, 4 flats and 5 longs needed to model the number.