Answer:
0.0548
Step-by-step explanation:
The distribution of life span for a certain type of battery is approximately normal with mean 2.5 hours and standard deviation 0.25 hour.
To find the the probability that a selected battery will have a life span of at most 2.1 hours, we need to first determine the z-score for x=2.1 hours using
We substitute the values to get:
We read read -1.6 from the standard normal distribution table to get:
P(X≤2.1)=0.0548
Answer:
<em>Answer: c) S=20R+60</em>
Step-by-step explanation:
<u>Linear Model</u>
The chart supplied shows the number of rows (R) in an auditorium and the total of seats (S).
We'll find the equation that relates them. The equation of a line can be expressed in the slope-intercept form:
S = mR + b
Where m is the slope and b is the intercept.
The slope is found by:
We'll use two sample points (20,460) and (45,960):
m = 20
The value of b can be found by using one of the points, for example (20,460), and having m=20:
460 = 20*20 + b
Thus: b = 460 - 400 = 60.
The equation is:
S = 20R + 60
You can test the other points and check they belong to the same line.
Answer: c) S=20R+60