Answer:
71.123 mph ≤ μ ≤ 77.277 mph
Step-by-step explanation:
Taking into account that the speed of all cars traveling on this highway have a normal distribution and we can only know the mean and the standard deviation of the sample, the confidence interval for the mean is calculated as:
≤ μ ≤ 
Where m is the mean of the sample, s is the standard deviation of the sample, n is the size of the sample, μ is the mean speed of all cars, and 
is the number for t-student distribution where a/2 is the amount of area in one tail and n-1 are the degrees of freedom.
the mean and the standard deviation of the sample are equal to 74.2 and 5.3083 respectively, the size of the sample is 10, the distribution t- student has 9 degrees of freedom and the value of a is 10%.
So, if we replace m by 74.2, s by 5.3083, n by 10 and 
by 1.8331, we get that the 90% confidence interval for the mean speed is:
≤ μ ≤ 
74.2 - 3.077 ≤ μ ≤ 74.2 + 3.077
71.123 ≤ μ ≤ 77.277
Answer:
x = 49
Step-by-step explanation:
Let's solve for x in the first triangle by applying the leg rule.
Leg rule is given as: hypotenuse/leg = leg/part
Hypotenuse = x
Leg = 28
Part = 16
Plug in the values into the equation
x/28 = 28/16
Cross multiply
x*16 = 28*28
16x = 784
x = 784/16
x = 49
✔️Let's check our answer to see if we would get the same value of x for the other triangle. Apply the same leg rule.
Hypotenuse = x
Leg = 21
Part = 9
Thus:
x/21 = 21/9
Cross multiply
x*9 = 21*21
9x = 441
x = 441/9
x = 49
✔️We have the same value. Therefore, x = 49 is the correct answer.
About 2.1 cases so it maybe 2 full cases. Hope this helped!
Answer:
You would graph it like this.
Step-by-step explanation:
Here's a tip! Use demos! It's free and you can graph equations and points and it tell you how to graph it.
