Answer:
The third score must be larger than or equal to 72, and smaller than or equal 87
Step-by-step explanation:
Let's name "x" the third quiz score for which we need to find the values to get the desired average.
Recalling that average grade for three quizzes is the addition of the values on each, divided by the number of quizzes (3), we have the following expression for the average:

SInce we want this average to be in between 80 and 85, we write the following double inequality using the symbols that include equal sign since we are requested the average to be between 80 and 85 inclusive:

Now we can proceed to solve for the unknown "x" treating each inaquality at a time:

This inequality tells us that the score in the third quiz must be larger than or equal to 72.
Now we study the second inequality to find the other restriction on "x":

This ine
quality tells us that the score in the third test must be smaller than or equal to 87 to reach the goal.
Therefore to obtained the requested condition for the average, the third score must be larger than or equal to 72, and smaller than or equal 87:
Answer:
t = 1.025c + 5.99
Step-by-step explanation:
Recall : general for of a linear equation is given by :
y = mx + c
Given the following :
Item cost = c
Shipping charge = $5.99
Tax on purchases = 2.5%
Total cost, t
t = c + tax + shipping cost
Tax on purchase : 2.5% * item cost ; 0.025c
Shipping = $5.99
Hence,
Total cost, t = c + 0.025c + 5.99
t = 1.025c + 5.99
Answer:
H 0 : p ≤ 0.4 H a : p > 0.4
And based on the alternative hypothesis we can conclude that we have a right tailed test
Step-by-step explanation:
Data given
n=300 represent the random sample size
estimated proportion of people with cats
is the value that we want to test
represent the significance level
z would represent the statistic
represent the p value
Null and alternative hypothesis
We want to test if the true proportion of people with cats is higher than 0.4, so then the best alternative is:
Null hypothesis:
Alternative hypothesis:
H 0 : p ≤ 0.4 H a : p > 0.4
And based on the alternative hypothesis we can conclude that we have a right tailed test
The statistic is given by:
(1)
Replacing we got:
I believe it is the second option.
Hope this helps :)