Answer:
What are the signs between the numbers?
Step-by-step explanation:
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:
6.7013x10⁸ km
Step-by-step explanation:
670,130,000 km
=6.7013x10⁸ km
Answer:
x = 1.5
y = 3
Step-by-step explanation:
to solve this system of equation using the substitution methods we say let
2x+3y=12................................... equation 1
y=x+1.5..................................... equation 2
substitute equation 2 into equation 1
2x+3y=12................................... equation 1
2x + 3( x + 1.5) = 12
2x + 3x + 4.5 = 12
5x + 4.5 = 12
collect the like terms
5x = 12 - 4.5
5x = 7.5
divide both sides by the coefficient of x which is 5
5x/5 = 7.5/5
x = 1.5
put x = 1.5 into equation 2
y=x+1.5..................................... equation 2
y = 1.5 + 1.5
y = 3
therefore the value of x = 1.5 and y = 3 respectively.