Please mark this as the brainliest
the correct answer is 1.4
Answer:

Step-by-step explanation:
The computation of the thickness of tire rubber for every lost 1,000 driven is shown below:
Data provided in the question
Inches of tread = 
In case of replaced = 
Based on the above information
Now in 40,000 miles, the ratio is

And for every 1,000 miles driven, the thickness is

hence, the thickness of tire rubber is 
The slope of the line is -1
The answer for it has to be 5 because 5*8=40 and 5*10=50 so its 5
Simplified to its simplest form would be 15/4. The GCD of them all would 400, so you divided them by 400.