Answer:

23 fire extinguisher.
Explanation:
Let x be the number of fire extinguishers.
We have been given that one fire extinguisher be available for every 6,000 square feet in a building. So the total area covered by x extinguisher will be 6,000x.
Since the building has an area of 135,000 square feet. This means that that total area covered by x extinguisher is 135,000 square feet. We can represent this information in an equation as:

Therefore, the equation
represents the number of fire extinguishers needed for a building that has 135,000 square feet.
Now we will solve for by dividing both sides of our equation by 6000.



Since we can not have 0.5 of a fire extinguisher, so we will round up our answer as:

Therefore, 23 fire extinguisher are needed for the building.