Answer:
standard error = 2.11
Step-by-step explanation:
First we stablish the data that we have for each sample:
<u>Population 1</u> <u>Population </u>2
n₁ = 100 n₂ = 90
x¯1= 95 x¯2 = 75
σ₁ = 14 σ₂ = 15
To calculate the standard error of each sample we would use the formulas:
σ = σ₁/√n₁
σx¯2 = σ₂/√n₂
Now, in order to obtain the standard error of the differences between the two sample means we combine those two formulas to obtain this:
σx¯1 - σ x¯2 = √(σ₁²/n₁ + σ₂²/n₂ )
So as you can see, we used the square root to simplify and now we require the variance of each sample (σ²):
σ₁² = (14)² = 196
σ₂² = (15)² = 225
Now we can proceed to calculate the standard error of the distribution of differences in sample means:
σx¯1 - σx¯2 = √(196/100 + 225/90) = 2.11
This gives an estimate about how far is the difference between the sample means from the actual difference between the populations means.
Answer:
Step-by-step explanation:
Step-by-step explanation:
You use the I = PRN formula
P = 11 500
R = 7.25% but you have to 7.25 divide by 100 so it becomes a decimal so it should be 0.0725
N = 2 years and 6 months. This can be 2.5 years because half of 12 is 6
the solution is 11 500 × 0.0725 × 2.5 = 2084.38
None of these are choices, because in order to make 20ths equal a 45th, it was to end in a 20,40,60,80, or ending in 00.
The last part answers the first part for you, just look at the y-values.
In other words:
<em>A'</em><em> </em>(-8, 2)
<em>B'</em> (-4, 3)
<em>C'</em> (-2, 8)
<em>D'</em> (-10, 6)
Explanation:
When you reflect any point over the x-axis, the y-value of the ordered pair is going to change.
This makes sense especially considering that the x-axis is horizontal, so the only way you could cross is to move up or down. If you were to move left or right, you'd only be able to cross the y-axis, since it's vertical.
Now for the last part, as I mentioned above, if you are reflecting across the y-axis, the x-values of the ordered pair is going to change.
<em>A'</em><em>'</em> (8, 2)
<em>B'</em><em>'</em> (4, 3)
<em>C'</em><em>'</em> (2, 8)
<em>D'</em><em>'</em> (10, 6)
Take note that the only thing that changes for the respective value is its sign, while the number itself stays the same.