The confidence interval is

. This means that we can be 99% confident that the mean number of books people read lies between 9.15 and 11.85.
To find the confidence interval, we first find the z-score associated with it:
Convert 99% to a decimal: 0.99
Subtract from 1: 1-0.99=0.01
Divide by 2: 0.01/2 = 0.005
Subtract from 1: 1-0.005 = 0.995
Using a z-table (http://www.z-table.com) we see that this is associated with a z-score between 2.57 and 2.58. Since both are equally far from this value we will use 2.575.
We calculate the margin of error using

This means that the confidence interval is

The lower limit is given by 10.5-1.35 = 9.15.
The upper limit is given by 10.5+1.35 = 11.85
4.25 is the correct answer
Answer:
Yoko bought 5 pounds of coffee.
If you want the steps, let me know. Hope this helps!!
Step-by-step explanation:
Shape: the form of an object
Outline: the line by which a figure or object is defined or bounded
Center: Point that is equal distances from any point of the circle
Spread: the measure of how far the numbers in a data set are away from the mean or the median