Answer:3
Step-by-step explanation:
The answer is B, you should really learn how to calculate these yourself though because they come up a lot.
We cannot calculate the confidence interval without the sample size. However, for the second question, the sample size needed would be 49.
The formula we use is

To find the z-score:
Convert 98% to a decimal: 0.98
Subtract from 1: 1-0.98 = 0.02
Divide by 2: 0.02/2 = 0.01
Subtract from 1: 1-0.01 = 0.99
Using a z-table (http://www.z-table.com) we see that this value is closest to a z-score of 2.33.
Using the z-score, our standard deviation (9) and our margin of error (3), we have:
Answer:
- 1) y = 13.5x + 1
- 2) y = 12x + 4
- 3) Sam won the race
Step-by-step explanation:
<h3>Part 1</h3>
Sam's car is 1 ft in front of the start line and its speed is 13.5 ft/s.
<u>The distance after x seconds is:</u>
<h3>Part 2</h3>
Alice's car the speed 12 ft/s and after 3 seconds is 40 ft in front of the start line.
<u>The distance after x seconds is:</u>
- y = 12(x - 3) + 40 = 12x - 36 + 40 = 12x + 4
<h3>Part 3</h3>
<u>After 15 seconds the distance from the start line is:</u>
- Sam ⇒ y = 13.5*15 + 1 = 203.5 ft
- Alice ⇒ y = 12*15 + 4 = 184 ft
As we see Sam is further from the start line than Alice