Answer:
(1)
Replacing the info given we got:
Step-by-step explanation:
Information given
represent the sample mean
represent the sample standard deviation
sample size
represent the value to verify
represent the significance level
t would represent the statistic
represent the p value
Hypothesis to test
We want to test if the true mean is higher than 9.33, the system of hypothesis would be:
Null hypothesis:
Alternative hypothesis:
The statistic is given by:
(1)
Replacing the info given we got:
Answer: −6+7
Step-by-step explanation: Trust
Answer:
1832 miles
Step-by-step explanation:
First we need to find the angle between the routes of the planes.
If one is N30°W and the other is S45°W, we can find the angle between the routes with the following equation:
30 + angle + 45 = 180
angle = 105°
Then, we need to find the distance travelled by each plane, using the formula:
distance = speed * time
The time is 1.5 hours, so we have that:
distance1 = 800 * 1.5 = 1200 km
distance2 = 750 * 1.5 = 1125 km
Now, to find the distance between the planes, we can use the law of cosines:
distance^2 = 1200^2 + 1125^2 - 2*1200*1125*cos(105)
distance^2 = 3356214.43
distance = 1832 miles
Step-by-step explanation:
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First square both sides to get:
c + 22 = (c + 2)^2
or
c + 22 = c^2 + 4c + 4
Move the terms on the left side to the right side:
c^2 + 3c - 18 = 0
Factor to get:
(c + 6) * (c - 3) = 0.
The solutions are c = -6 and c = 3.
Check to see if these answers work by plugging them into the original equation:
c = -6:
sqrt (-6 + 22) ?= -6 + 2
But, -6 + 2 is a negative number, and you can't get a negative from a square root. So, -6 is extraneous.
c = 3:
sqrt (3 + 22) ?= 3 + 2
5 = 5. So, 3 works.
The answer is: B
