Answer:
0.2839 = 28.93%
Step-by-step explanation:
In order to find find the probability that one car chosen at random will have less than 68.5 tons of coal, we have to find z
Le x be tons of coal in a car
Z = (x – mean)/standard deviation
Z = (x – μ)/ σ
P (x<68.5) = P(z < (68.5-69)/0.9)
P (x<68.5) = P(z < -0.5555)
Then we use the z table to find the area under the curve.
P (x<68.5) = 0.2893
Answer:
y + 7 = - 
(x - 1)
Step-by-step explanation:
The equation of a line in point- slope form is
y - b = m(x - a)
Where m is the slope and (a, b) a point on the line
Here m = - and (a, b) = (1, - 7), thus
y - (- 7) = - (x - 1), that is
y + 7 = - (x - 1) ← in point- slope form
Answer:
7.4 miles per hour
Step-by-step explanation:
To find her speed in miles per hour, divide the amount of miles she ran by the number of hours:
5.55/0.75
= 7.4
So, her speed is 7.4 miles per hour
Answer:
15
Step-by-step explanation:
Rate of change is the slope of the tangent which will be the derivative of the function
if f(x) = 3x² - 4
f'(x) = 6x
as the derivative is linear, the average rate of change will occur at the midpoint of the interval
f'(2.5) = 6(2.5) = 15
