A sample of Brand A of automobile tires has a mean lifespan of 35,000 miles and a standard deviation of 2,500 miles. Assume the lifespans of the tires have a bell-shaped distribution. a. Between what 2 values does 95% of all tires have for a lifespan?
b. What percentage of tires have a lifespan of 37,500 to 40,000 miles?
c. What is the z-value for a tire whose lifespan is 28,000?
d. If 50 more tires were added to the sample, how many would have a lifespan of
less than 32,500 miles?
e. If Brand B tires has a mean lifespan of 38,000 miles and a standard deviation of
6,000 miles, which brand would you choose, and why?

i believe that the slope of the line is -5

step-by-step explanation:

2y+y=5

add 2y and y

proportions are fractions that equal to each other. so if two fractions are the same, they are proportional.

let's check the answers to see if they are proportional.

question a is not proportional because you can't turn 1.5/3 to 3/9. if you try to multiply 1.5/3 by 2 or 3, you wont get 3/9. it's impossible to make the fractions the same.

question b is not proportional because you can't turn 22/33 to 4/6. 33 can't go into 6.

question c is proportional because when you multiply 2 and 3 by 71, you would get 142/213, and those fractions equal to each other

question d is proportional because when you divide 14 and 7 by 2, you would end up with 7/3.5, and those fractions equal to each other.