Answer:
Using the ratio and proportion method, we find that on an average 1.875 rooms can be painted per gallon.
Step-by-step explanation:
Concept: Use the method of ratio and proportion.
In this method, if a relationship is given between two values, then using that relationship we can find another relationship with respect to another variable.
Given that for 2/5 gallons of paint, we can paint 3/4 of rooms. So, for one gallon of paint, divide 2/5 by 3/4.
2/5 gallons of paint = 3/4 rooms
1 gallon of paint = [tex]\frac{\frac{3}{4} }{\frac{2}{5} } = \frac{15}{8} =1.875[/tex] rooms
So, on an average they can paint 1.875 rooms per gallon.
For more explanation, refer the following link
https://brainly.com/question/11243787
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