7 lb will cover an area of 1 square foot, while 315 lb will cover an area of 45 square feet.
From given question,
252 lb = 36 ft²             ..........(1)
The number of pound for an area of 1 square foot is calculated as follows:
x = 1 ft²                       .......(2)
The area and the amount of gravel are illustrations of proportions.
From (1) and (2) we get an equation,
⇒ x × 36 = 252 × 1
⇒ x = 252/36
⇒ x = 7 lb
We need to find the area that could be covered with 315 lb of gravel
The area to be covered with 315 lb gravel is calculated as follows:
 315 lb = y               ............(3)
From (1) and (3) we get an equation,
⇒ y × 252 = 36 × 315
⇒ y = 45 ft²
Therefore, 7 lb will cover an area of 1 square foot, while 315 lb will cover an area of 45 square feet.
Learn more about the proportions here:
brainly.com/question/13114933
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Answer:
2km/m
Step-by-step explanation:
6 laps = 10km
(because 3 x 2 = 6 and double 5km as well)
Distance divide time = speed
20 mins divided by 10km = 2km per minute
 
        
             
        
        
        
Answer: 
30
Step-by-step explanation:
62 = 2x+2
62-2 = 60
60/2 = 30