Final answer:
To find out how many gallons are needed to paint 21 offices, calculate the amount of paint per office by dividing 8 gallons by 3, and then multiply by 21 to get approximately 56 gallons.
Step-by-step explanation:
The student is asking how many gallons of paint are needed to paint 21 offices, given that 8 gallons are required for 3 offices. To find the answer, we need to set up a proportion because the number of offices is directly proportional to the amount of paint needed.
Given that 8 gallons are needed for 3 offices, we can calculate the gallons needed for one office by dividing 8 by 3. Then, to find out how many gallons are needed for 21 offices, we can multiply the gallons needed for one office by 21.
The calculation is as follows:
- Calculate the gallons per office: 8 gallons ÷ 3 offices = 2.67 gallons per office
- Multiply the gallons per office by the number of offices: 2.67 gallons/office × 21 offices = 56.07 gallons
Therefore, it will take approximately 56 gallons of semi-gloss paint to paint 21 offices of the same size.