Answer:
Step-by-step explanation:
Let
p ----> the price of a watermelon in dollars
w ---> the weight of a watermelon in pounds
In this problem we have a proportional relationship
Remember that
A relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form
or
In a proportional relationship the constant of proportionality k is equal to the slope m of the line and the line passes through the origin
In this problem
The value of the constant of proportionality k is the same that the unit rate
Find out the unit rate
Divide the total cost by the total weight

substitute in the equation
Approximately 2 gallons will be needed if each gallon of stain and the project will cost be $73.96 if each gallon costs $36.98
<h3>How to find the area of a triangle</h3>
The formula for calculating the area of a triangle is expressed as:
A = 0.5bh
where
base = 15feet
height = 20feet
Area of the deck = 20 * 15 * 0.5
Area of the deck is 150 square feet
Number of gallons needed = 350/150 = 2.3
Hence approximately 2 gallons will be needed if each gallon of stain covers a maximum of 350 square feet.
Cost of the two gallons = 36.98 * 2
Cost of the two gallons = $73.96
Hence the project will cost be $73.96 if each gallon costs $36.98
Learn more on area of a triangle here: brainly.com/question/23945265
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