To find the average: the sum of the values/number of values
=250+310+275+195/4
=257.5
Answer:
Explained below.
Step-by-step explanation:
(1)
The confidence level is, 91%.
Compute the value of α as follows:

(2)
As the population standard deviation is provided, i.e. <em>σ</em> = 256 psi, the <em>z</em> value would be appropriate.
The <em>z</em> value for α = 0.09 is,
<em>z</em> = 1.69
(3)
Compute the 91% confidence interval as follows:


(4)
The 91% confidence interval for population mean implies that there is a 0.91 probability that the true value of the mean is included in the interval, (2942.29, 3057.71) psi.
Answer:she will have $25 left .
Step-by-step explanation:
0.25(60) = 15
$40 - $15 = $ 25
None of them will get into a negative number. When you have like "2x" is the number twice, right? Some number has to be negative
Answer:
$15, $20
Step-by-step explanation:
Let u represent the unit price of umbrellas and h the unit price of hats.
Case 1: A. spent $80.
Then $80 = 4u + 5($4), or $80 = $20 + 4u, or $60 = 4u, or
u = $15/umbrella.
Case 2: A spent $100.
Then $100 = 4u + 5($4), or $100 = $20 + 4u, or $80 = 4u, or
u = $20/umbrella.
The least A. could have spent on a single umbrella was $15, and the most was $20.