I assume, that this pen is rectangular.
Look, that 48 = 24 * 2 = 12 * 2 * 2 = 3 * 2 * 2 * 2 * 2
And know choose these numbers and multiply!
First dimension: 3*2 x 2*2*2 = 6 x 8
Second: 3 x 2*2*2*2 = 3 x 16
Third: 3*2*2 x 2*2 = 12 x 4
Fourth: 3*2*2*2 x 2 = 24 x 2
Fifth: 48 x 1
Sixth dimension cannot be integer. So you can for example save this as
48 = 3 * 16 = 1.5 * 2 * 16 = 1.5 * 32
Sixth dimension: 1.5 x 32
NOTE: each dimensions are in feet!
Hmm... I would say the equation would look like 3+5x=72/4.
3+5x=72/4
3+5x=18
5x=18-3
5x=15
x=15/5
x=3
The number is 3
4 slices of pizza. You get this by dividing the total amount of slices but the amount of people.
Convert the mixed number into a decimal and multiply on a calculator (or by hand).