Answer:
3.4
Step-by-step explanation:
Standard deviation of a population is defined as:
σ² = ∑(xᵢ − μ)² / n
The standard deviation of a sample is defined as:
s² = ∑(xᵢ − x)² / (n - 1)
It's not clear which one we have, so let's calculate both.
First, we must find the mean.
μ = (5+12+15+10+12+6+8+8) / 8
μ = 9.5
Now we find the squares of the differences:
(5-9.5)² + (12-9.5)² + (15-9.5)² + (10-9.5)² + (12-9.5)² + (6-9.5)² + (8-9.5)² + (8-9.5)²
= 80
Divide by n:
σ² = 80 / 8
σ² = 10
And take the square root:
σ = √10
σ ≈ 3.2
That's not one of the answers, so let's try the standard deviation of a sample instead of a population.
Instead of dividing by n, we'll divide by n-1:
s² = 80 / 7
And take the square root:
s = √(80/7)
s ≈ 3.4
So that must be it.
Answer: GCF = x
Step-by-step explanation:
x(x^3/x + x^2/x + -6x/x)
x(x^2 + -6)
x(x - 2)(x + 3)
Answer:
1) The probability that the mean mpg for a random sample of 25 light vehicles is 0.042341.
2) between 20 and 25 --> 21-25/2.9 = -1.38
Step-by-step explanation:
Problem #1:
- Using the z-score formula, z = (x-μ)/σ/n, where x is the raw score = 20 mpg,μ is the population mean = 21 mpg , σ is the population standard deviation = 2.9, n = random number of samples.
<h3><u>X < 20</u></h3>
- = z = 20 - 21/2.9/√25
- = z = -1/2.9/5
- = z = -1.72414
<h2><u><em>Now</em></u></h2>
<em>P-value from Z-Table:</em>
<h3><u>P(x<20) = 0.042341</u></h3>
Problem #2:
<h3>21-25/2.9 = -1.38</h3>
