Answer and Step-by-step explanation:
we have the following data:
Point estimate = sample mean = \ bar x = 12.39
Population standard deviation = \ sigma = 3.7
Sample size = n = 177
a) the margin of error with a 90% confidence interval
α = 1 - 90%
alpha = 1 - 0.90 = 0.10
alpha / 2 = 0.05
Z \ alpha / 2 = Z0.05 = 1,645
Margin of error = E = Z \ alpha / 2 * (\ sigma / \ sqrtn)
we replace:
E = 1.645 * (3.7 / \ sqrt177)
Outcome:
E = 0.46
b) margin of error with a 99% confidence interval
α = 1-99%
alpha = 1 - 0.99 = 0.01
alpha / 2 = 0.005
Z \ alpha / 2 = Z0.005 = 2,576
Margin of error = E = Z \ alpha / 2 * (\ sigma / \ sqrtn)
we replace:
E = 2,576 * (3.7 / \ sqrt177)
Outcome:
E = 0.72
c) A larger confidence interval value will increase the margin of error.
y = x + 4/x
replace x with -x. Do you get back the original equation after simplifying. if you do, the function is even.
replace y with -y AND x with -x. Do you get back the original equation after simplifying. If you do, the function is odd.
A function can be either even or odd but not both. Or it can be neither one.
Let's first replace x with -x
y = -x + 4/-x = -x - 4/x = -(x + 4/x)
we see that this function is not the same because the original function has been multiplied by -1
. Let's replace y with -y and x with -x
-y = -x + 4/-x
-y = -x - 4/x
-y = -(x + 4/x)
y = x + 4/x
This is the original equation so the function is odd.
Answer:
$238.33
Explanation:
Assume that the amount you need to save per month is x.
You will be saving monthly for 12 years. This means that the amount you will save after 12 years is:
amount saved after 12 years = 12 * 12 * x = 144x
Now, you need to save 20% of $<span>171,600.00. We will first need to calculate this value.
20% of $</span>171,600.00 = 0.2 * <span>171,600.00 = $34320
Now, to know your monthly savings, equate the total amount saved in 12 years with the amount that needs to be saved and solve for x as follows:
144x = 34320
x = 34320 / 144
x = 238.33
This means that, to meet your goal, you need to save $238.33 monthly for 12 years.
Hope this helps :)</span>
Using the identity :
Cos (2a) = 1-2 Sin^2(a)
Therefore :<span>1−2 sin ^2 (22.5∘) = Cos(2a)
= Cos (2 * 22.5) = Cos 45</span>
Answer:
x - 9
Step-by-step explanation:
In this case, "simplify" directs that you 1) carry out the indicated multiplication and 2) combine like terms.
-3(x+3)+4x = -3x - 9 + 4x = x - 9
