X + (x + 2) + ( x + 4) + (x + 6)
----------------------------------- = 15
4
4x + 12
--------- = 15
4
Multiply by 4 on both sides
4x + 12 = 60
subtract 12 from both sides
4x = 48
divide by 4 on each side
x = 12
x + 2 = 14
x + 4 = 16
x + 6 = 18
Answer:
-6
Step-by-step explanation:
The equation is in slope intercept form
y = mx+b where m is the slope and b is the y intercept
The y intercept is the value when x = 0
The y value is -6 when the x value is 0
y = -4x+ (-6)
Answer:
a. 19.68 miles per gallon.
b. 26.32 miles per gallon.
Step-by-step explanation:
Mean gas mileage (μ) = 23.0 mpg
Standard deviation (σ) = 4.9 mpg
In a normal distribution, for any length X, the z-score is determined by the following expression:

In a normal distribution, the 25th percentile (first quartile) of a normal distribution has a corresponding z-score of z = -0.677 and the 75th percentile has a corresponding z-score of z = 0.677
a. The first quartile of the distribution of gas mileage is

19.68 miles per gallon.
b. The third quartile of the distribution of gas mileage is

26.32 miles per gallon.
Answer:
a)
b) 
c) 
Step-by-step explanation:
Part a
The significance level given is
and the degrees of freedom are given by:

Since we are conducting a right tailed test we need to find a critical value on the t distirbution who accumulates 0.1 of the area in the right and we got:

Part b
The significance level given is
and the degrees of freedom are given by:

Since we are conducting a left tailed test we need to find a critical value on the t distirbution who accumulates 0.01 of the area in the left and we got:

Part c
The significance level given is
and
and the degrees of freedom are given by:

Since we are conducting a two tailed test we need to find a critical value on the t distirbution who accumulates 0.025 of the area on each tail and we got:
