Lena plans to fill her 22-cm cube to within 2 cm of the top.How many cubic centimeters of dirt will Lena need?

I assume that your cube measures 22 by 22 by 22 cm.

The volume is:
22 * 22 * 20 = 9,680 cubic cm.

thank you, I understand now

You're welcome. :-)

To find out how many cubic centimeters of dirt Lena will need, we can calculate the volume of the 22-cm cube and subtract the volume of the empty space remaining at the top.

1. Calculate the volume of the 22-cm cube:
The volume of a cube is calculated by multiplying the length of one side by itself twice (L × L × L). In this case, the length of each side of the cube is 22 cm.
Volume of the cube = (22 cm) × (22 cm) × (22 cm) = 10648 cm³.

2. Calculate the volume of the empty space remaining at the top:
Since Lena plans to fill the cube to within 2 cm of the top, we need to find the volume of a smaller cube with sides measuring 18 cm (22 cm - 2 cm).
Volume of the empty space = (18 cm) × (18 cm) × (18 cm) = 5832 cm³.

3. Calculate the volume of dirt needed:
To find the volume of dirt, subtract the volume of the empty space from the volume of the cube.
Volume of dirt = Volume of the cube - Volume of the empty space = 10648 cm³ - 5832 cm³ = 4816 cm³.

Therefore, Lena will need 4816 cubic centimeters of dirt to fill her 22-cm cube to within 2 cm of the top.