Answer:
a) The margin of error for a 90% confidence interval when n = 14 is 18.93.
b) The margin of error for a 90% confidence interval when n=28 is 12.88.
c) The margin of error for a 90% confidence interval when n = 45 is 10.02.
Step-by-step explanation:
The t-distribution is used to solve this question:
a) n = 14
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 14 - 1 = 13
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 13 degrees of freedom(y-axis) and a confidence level of 
. So we have T = 1.7709
The margin of error is:
In which s is the standard deviation of the sample and n is the size of the sample.
The margin of error for a 90% confidence interval when n = 14 is 18.93.
b) n = 28
27 df, T = 1.7033
The margin of error for a 90% confidence interval when n=28 is 12.88.
c) The margin of error for a 90% confidence interval when n = 45 is
44 df, T = 1.6802
The margin of error for a 90% confidence interval when n = 45 is 10.02.
Answer:
we need the table!
Step-by-step explanation:
Answer:
thanks for the points
Step-by-step explanation:
have a nice day ahead
We know that all black beards cost the same money
And all red beards cost $25
And B represents number of black beards
And R represents number of red beards
We have been given the inequality 20B+25R > 350 to show the target for this month.
The above inequality shows that Merlin needs to make more than 350, hence he made 350 last month
Further, it shows that B has been multiplied by 20, hence the black beard's cost was 20
Answer:
x=±1. are the factors of the quadratic equation.
Step-by-step explanation:
Given quadratic expression, f(x)=-12x - 2x + 60x² +14x-60
Rearranging and adding the terms in the expression and equating to zero.
f(x)= 60x² -60=0
60(x² - 1) =0
The zero product property states that if the product of a⋅b=0 then either a or b equal zero or both of them must be equal to zero. This basic property helps us solve the quadratic equations like (x+2)(x-5)=0 where x =-2,5.
from the zero product property we can infer that 60≠0⇒x² - 1=0
⇒(x+1)×(x-1) = 0
⇒x=±1.
Therefore, x=±1. are the factors of the quadratic equation.
