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:
1. 31
2. -40
3. 28.5
4. 75
5. 6
6. -24
7. -34
8. 68
9. 8
10. 26
Step-by-step explanation:
I tried to do the best I can I hope this helps! :))
<h3>Y
ou have the correct answer</h3><h3>Interest rate = 21.5%</h3>
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Work Shown:
i = P*r*t .... simple interest formula
i = simple interest
i = 2075-1000 = 1075
P = 1000 = amount borrowed (principal)
r = unknown interest rate
t = 5 = time in years
So,
i = P*r*t
1075 = 1000*r*5
1075 = 5000r
5000r = 1075
r = 1075/5000
r = 0.215
r = 21.5%
The area of a triangle is base x height/2,
so all you have to do is multiply 6x20 to get 120 and then divide that by 2 to get 60 m squared!! :)
The interquartile range is 12-6=6