Question

Ethan has partially filled the prism with 8 unit cubes.

How many more cubes does he need to fill the prism completely
A:10
B:15
C:19
D:21
Help me please!!!???!

Answer 1

3 units across would add to 9 and 3 units up would add to 9

Answer 2

Complete Question

A rectangular prism with length, height, and width of 3. Ethan has partially filled the prism with 8 unit cubes. How many more cubes does he need to fill the prism completely?

Answer:

(C)19

Explanation:

The Volume of the Prism = Length X Height X Width

=3 X 3 X 3

=
`27 \:cubic\:units`

Volume of the Unit Cube =
`s^3=1^3=1 \:cubic \: units`

Number of cubes that will fit into the prism= Volume of Prism ÷ Volume of the Cube

=27 ÷ 1=27 cubes

Since Ethan has partially filled the prism with 8 unit cubes.

Number of Cubes required to fill the prism = 27-8

=19 Cubes