In this
problem, the given values are:
x = average =
30.4
s = standard
deviation = 7.1
n = number of
samples = 25
Degrees of
freedom = n -1 =24
Using the
t-distribution table for a normal curve at 90% CI, we get t-crit:
t-crit = 1.711
Now the Margin
of Error (E) is calculated as:
E = t-crit*(s/ 
)
By substituting the known values into the equation:
E = 1.711 * (7.1/ 
)
E = +- 4.30
Therefore, the margin of error is 4.36. Hence, the commute time
is between 26.1 minutes and 34.7 minutes.
<span> </span>
Answer:
6.6.6
Step-by-step explanation:
anything to the 3rd power is a perfect cube
6.6.6=6^3 = a perfect cube
Answer:
x = 3 is extraneous
Step-by-step explanation:
Given
= x - 5 ( square both sides to clear the radical )
4x - 8 = (x - 5)² ← expand using FOIL
4x - 8 = x² - 10x + 25 ( subtract 4x - 8 from both sides )
0 = x² - 14x + 33 ← in standard form
0 = (x - 11)(x - 3) ← in factored form
Equate each factor to zero and solve for x
x - 11 = 0 ⇒ x = 11
x - 3 = 0 ⇒ x = 3
As a check
Substitute these values into the equation and if both sides are equal then they are solutions
x = 11
left side = 
= 
= 6
right side = 11 - 5 = 6
Thus x = 11 is a solution
x = 3
left side = 
= 
= 2
right side = 3 - 5 = - 2 ≠ 2
Thus x = 3 is an extraneous solution
Answer:
-19
Step-by-step explanation:
f(x) = -11 + 8x
f(-1) =-11 + 8(-1)
= -11 -8
= -19
