This is going to require a good bit of division. I am going to turn the mixed fractions into improper fractions. Remember that to divide fractions, you take the 2nd fraction, flip it, and multiply.
First (2 1/2)/(1/4) = (5/2)(4) = 20/2 = 10
Next, 3/(1/4) = 3(4) = 12
Lastly, (3 1/4)/(1/4) = (13/4) x 4 = 52/4 = 13
This means we need 10 rows of 12, 13 high. 10(12)(13) = 1560 cubes.
