Answer:

Step-by-step explanation:
<u>Confidence Interval</u>
When the population standard deviation
is known, the formula for a confidence interval for a population mean
is:

Where n is the sample size and z is the corresponding z-value from the standard normal distribution for the selected confidence level. The value of z for a 95% confidence interval is z=1.96. The rest of the values are

Calculating the confidence interval


Or, equivalently

Answer:
482 km
63.94 degrees
Step-by-step explanation:
to solve this question we will use the cosine rule. For starters, draw your diagram. From point A, up north is 500km and 060 from there, another 300. If you join the point from the road junction back to the starting point, yoou have a triangle.
Cosine rule states that
C = 
where both A and B are the given distances, 500 and 300 respectively, C is the 3rd distance we're looking for and c is the given angle, 060
solving now, we have
C = 
C = ![\sqrt{250000 + 90000 - [215000 cos(60) }]](https://tex.z-dn.net/?f=%5Csqrt%7B250000%20%2B%2090000%20-%20%5B215000%20%20%20cos%2860%29%20%20%7D%5D)
C = ![\sqrt{340000 - [215000 * 0.5 }]](https://tex.z-dn.net/?f=%5Csqrt%7B340000%20-%20%5B215000%20%2A%200.5%20%20%7D%5D)
C = ![\sqrt{340000 - [107500 }]](https://tex.z-dn.net/?f=%5Csqrt%7B340000%20-%20%5B107500%20%20%7D%5D)
C =
C = 482 km
The bearing can be gotten by using the Sine Rule.
= 
sina/500 = sin60/482
482 sina = 500 sin60
sina = 
sina = 0.8983
a = sin^-1(0.8983)
a = 63.94 degrees
I'm assuming that when you wrote "(7x/2-5x+3)+(2x/2+4x-6)," you actually meant "<span>(7x^2-5x+3)+(2x^2+4x-6). Correct me if I'm wrong here.
</span><span>+(7x^2-5x+3)
</span><span>+(2x/2+4x-6)
-------------------
=9x^2 - x - 3 (answer) </span>
Answer:
D
Step-by-step explanation:
I have answers to whole packet:
1.D
2.A
3.C
4.D
5.C
6.D
7.A
8.C
9.A
10.B
11.A
12.A
13.A
14.B
15.A
16.B
17.A
18.A
19.B
20.C
21.A
22.A
23.D
24.B
Answer:
Casy
Step by step explanation:
You divide the miles by their time
It took Jessica 6 minutes and .03 seconds to finish a mile
It took Casy 5 minutes and 54 seconds to finish a mile
Casy is .09 Seconds quicker than Jessica