Question

Thea builds the first layer of a rectangular prism using 4 unit cubes raj adds 4 more layers how many unit cubes are used?

Answer 1

Given:
Thea makes the 1st layer of 4 unit cubes
Raj adds 4 more layers

There is a total of 5 layers with 4 unit cubes each layer.

5 x 4 = 20 unit cubes

There are 20 unit cubes used in building a rectangular prism.

Answer 2

20 unit cubes were used.

Explanation:

Thea builds the first layer of a rectangular prism with 4 unit cubes.

Raj added 4 more layers so total five layers were there to build a new prism. Now we have to calculate total number of cubes used.

By unitary method

∵ One layer of rectangular prism used number of cubes = 4

∴ 5 layers of prism will use cubes = 5×4 = 20 unit cubes

Total 20 unit cubes were used.