Mu=80, sigma=39, X=85
Z=(X-mu)/sigma = 5/39=0.128=0.13
P(X<=85)= 0.5517 (from Z-table)
so, P(X>85)=1-0.5517=0.4483 approx. thats 44.8% probability.
The slope of the given line is the coefficient of x, 3/5. The slope of the perpendicular line will be the negative reciprocal of that: -1/(3/5) = -5/3.
The point-slope form of the equation for a line of slope m through point (h, k) can be written ...
... y = m(x -h) +k
For your point and the slope found above, this becomes
... y = (-5/3)(x -15) -5
When x=0, this is
... y = (-5/3)(-15) -5 = 20
The y-intercept is 20.
Using proportions, it is found that Ermias is traveling at a rate of 11 mph and Jeremiah at a rate of 19 mph.
<h3>What is a proportion?</h3>
A proportion is a fraction of a total amount, and the measures are related using a rule of three.
Jeremiah travels 8 mph faster than Ermias, hence their velocities are:
x, x + 8
They travel in opposite directions, hence in one hour they are 2x + 8 apart.
In eight hours, the distance is 8(2x + 8), which is of 240 miles, hence:
8(2x +8) = 240
2x + 8 = 30
2x = 22
x = 11.
Then:
- x = 11 + 8 = 19 -> Jeremiah.
More can be learned about proportions at brainly.com/question/24372153
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