Arectangular prism has a length of 12 in., a width of 5 in., and a height of 4 1/4 in. the prism is filled with cubes that have edge lengths of 1/4 in. how many cubes are needed to fill the rectangular prism?

V = L * W * H
L = 12
W = 5
H = 4.25
V = 255 cu in

Volume of small cubes = 1/4 * 1/4 * 1/4 = 1/64

Number needed = volume of large cube / volume of small cube
Number needed = 16320. 
This answer does not answer whether or not you get a possible prism.

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