Answer:
(22.0297, 23.3703)
Step-by-step explanation:
Given that an economist wants to estimate the mean per capita income (in thousands of dollars) for a major city in California.
Let X be per capita income (in thousands of dollars) for a major city in California.
Mean = 22.7
n = 183
Population std dev = 6.3
Since population std dev is known we can use Z critical value.
Std error =
Z critical =1.44
Marginof error = ±1.44*0.4657=0.6706
Confidence interval 85%
=
Answer:
Step-by-step explanation:
The initial temperature difference of 72 -34 = 38 °F is reduced to a difference of 72 -41 = 31 °F after 35 minutes. The exponential term in the temperature expression could have the factor ...
(31/38)^(t/35) = e^(-kt)
Taking the natural log, we find ...
(t/35)ln(31/38) = -kt
k = ln(38/31)/35 ≈ 0.00581711
To the nearest thousandth, this is ...
k ≈ 0.006
Using this in the equation for temperature, we have ...
T = 72 -38e^(-0.006t)
Filling in the desired value for t (80), we find the turkey temperature after 80 minutes to be about
T = 72 -38e^(-.006×80) = 72 -38e^-.48 ≈ 48.49
T ≈ 48 °F
The value of k is about 0.006, and the turkey temperature is about 48 °F.
