Unsaved?
Anyway, 60,000 is one standard deviation above the mean. By the 68-95-99.7 rule 68% of the probability is between -1 and +1 standard deviations, so 34% between 0 and 1 sigma so 50%-34%=16% above one sigma.
Answer: 16%
Let A be the speed of hiker A and B the speed of hiker B.
let's say that B is faster than A, so B=A+0.5
we know that they met after 2 hours, and the distance each walked after 2 hours is given by:

One of the hikers travels at 4 miles per hour, the other one at 4.5 miles per hour
As per given by the question,
There are given that four point.
The point is,

Now,
From given point,

Then, the factor is,

Now, solve the above equation,

The factorial formd will be,

Now, find the value of "a" with the help of given point (0, -8).
So,
Puth the value of x =0, and y=-8 in above equation,
Then,

Then, a=2.
Now,
The value of a is 2.
And,
The polynomial in the factored form is,

Hence, the value of a is 2 and the polynomial in the factored form is,