Answer: 50 brick
In this case, you are given the concrete volume and the brick length(10inch), width(9 inch) and height(4inch). To answer this question, you need to know the brick volume. The calculation would be:
Brick volume= length x width x height= 10 x 9 x 4= 360 inch cubic.
Then to know how many bricks made, the calculation would be:
Brick made= concrete volume/ brick volume
Brick made= 18000inch cubic/ 360 inch cubic= 50 brick