Aprism is filled with cubes that have edge lengths of 1/4 in. how many cubes are needed to fill the rectangular prism

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.

The answer would be choice b