Take away m from both sides to get 15=2m-9 and add 9 to get 24=2m, next divide by 2 to get m=12
Answer:
a) 
b) 
If we compare the p value and the significance level given we see that 
we have enough evidence to reject the null hypothesis at 5% of significance.
Step-by-step explanation:
Data given and notation
n=114 represent the random sample taken
estimated proportion of people that their approval rating might have changed
is the value that we want to test
represent the significance level
Confidence=95% or 0.95
z would represent the statistic (variable of interest)
represent the p value (variable of interest)
Hypothesis
We need to conduct a hypothesis in order to test the claim that true proportion of people that their approval rating might have changed is 0.58 or no.:
Null hypothesis:
Alternative hypothesis:
Part a
(1)
Calculate the statistic
Since we have all the info requires we can replace in formula (1) like this:
Part b: Statistical decision
The significance level provided . The next step would be calculate the p value for this test.
Since is a bilateral test the p value would be:
If we compare the p value and the significance level given we see that we have enough evidence to reject the null hypothesis at 5% of significance.
We have that El Paso is 320 miles from Tucson and 720 miles from San Diego.
You're travelling from Tucson to San Diego.
First we have to find the distance from Tucson to San Diego. We can do this by finding the difference between the distance of Tucson from San Diego and El Paso from San Diego.
That is:
720−320
400 miles
You leave by 6:00 am.
You drive for 75 miles per hour in 4 hours for the first part of the journey.
You then drive for 50 miles per hour for the rest of the journey.
The first step is to find the distance that the rest of the journey took. We can do that by first finding the distance covered in the first part of the journey and subtracting that from the total distance (400 miles).
To find the distance for the first part of the journey, we apply the formula for speed (rate of change of distance with time):
s = d/t
⇒d = s⋅t
where d= distance; t = time
Therefore:
d=75⋅4
d=300 miles
The first part of the journey covered 300 miles. This means that the rest of the journey covered:
400 - 300 = 100 miles
Now, to find the time the rest of the journey took, we have to apply the same formula for speed:
s=d/t
t=d/s
Therefore:
t=100/50
t=2 hrs
To find the total time it took to complete the journey, we have to add the times for the first part and the rest of the journey.
That is:
T=4+2
T=6 hours
Since you left home by 6:00 am, the time you will get to San Diego is 6 hours after that, i.e. 12 noon (Tucson time)
That is the answer.
