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:
To solve, we need to find the y-intercept (b). In order to find the y-intercept, we can plug in the slope and the (x,y) coordinate pair given to us into the equation to solve for the y-intercept:
y=mx+b
4=(-7/-2)*-2+b
4=14/-2+b
4=-7+b
Add 7 to both sides
b=11
Therefore the equation is:
(note that the fraction is positive since the two negatives cancel out)
I dont understand the question that you are asking
Answer: The mechanics spent about 8.5 hours working on the car
Step-by-step explanation: The total bill was $637, a portion of that being getting the parts which was $280. 637-280=357
357/42=8.5
Answer:
2 >
Step-by-step explanation:
Given:
- Felicity's dog eats two cups of dog food per day :2
If the amount of food that Martin's dog eats is represented by using m
Felicity's dog eats at least one-quarter cup more than one-half of the amount Martin's dog eats:
So we have the inequality represents the situation is:
2 >