Answer:
Step-by-step explanation:
(a) Option B cost less at 120 miles driven
The cost difference at 120 miles between option A and option B is $15
(b) Option A and B cost the same at driving 60 miles.
Option B would cost more if you drive less than 60 miles.
5+ 3 Well a times it would probably be 40
Answer:
The 90% confidence interval for the mean nicotine content of this brand of cigarette is between 20.3 milligrams and 30.3 milligrams.
Step-by-step explanation:
We have the standard deviation for the sample, so we use the t-distribution to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 9 - 1 = 8
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 8 degrees of freedom(y-axis) and a confidence level of
. So we have T = 1.8595
The margin of error is:
M = T*s = 1.8595*2.7 = 5
In which s is the standard deviation of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 25.3 - 5 = 20.3 milligrams
The upper end of the interval is the sample mean added to M. So it is 25.3 + 5 = 30.3 milligrams.
The 90% confidence interval for the mean nicotine content of this brand of cigarette is between 20.3 milligrams and 30.3 milligrams.
Answer:
7 feet is the length of the blade of the windmill.
Step-by-step explanation:
We have the equation
h = 7 sin(pi/21t) + 28 ------ eq1
At time 't' = 0, the end of the blade is pointing to the right parallel to the ground meaning it is at the same height as the other end. (Ф = 0°)
So, by calculating the maximum height of this end at Ф = 90°. we can calculate the length of the blade.
Now, we know that a general model equation of a circular simple harmonic motion is represented as : y = A sinωt + k ----- eq2
Where A is the amplitude that is, maximum displacement from mean to maximum position.
ω is the angular frequency.
Comparing eq1 and eq2:
A = 7
so the difference in blades end height at Ф = 0° and Ф = 90° is 7 feet.
Hence, the length of the blade is 7 feet.
Answer:
-x > -5
Step-by-step explanation:
Let's start with a positive number less than 5.
4<5
likewise when applied to -x> -5
-4>-5