Answer:
They can paint 18. 66 sq ft with 3 gallons of paint.
Step-by-step explanation:
Total area painted = 280 sq ft
Total gallons of paint used = 45
So, 45 gallons of paint painted 280 sq ft.
⇒ By UNITARY METHOD,
1 gallon of paint paints sq ft
So, area painted by 1 gallon = 6.22 sq ft
⇒ area painted by 3 gallon = 6.22 sq ft x 3 = 18. 66 sq ft
So, they can paint 18. 66 sq ft with 3 gallons of paint.