Answer: (14.4, 17.2)
Step-by-step explanation: We are to construct a 98% confidence interval for mean household usage of electricity.
We have been given that
Sample size (n) = 872
Sample mean (x) = 15.8
Population standard deviation (σ) = 1.8
The formulae that defines the 98% confidence interval for mean is given below as
u = x + Zα/2 × σ/√n...... For the upper limit
u = x - Zα/2 × σ/√n...... For the lower limit
Zα/2 = critical value for a 2% level of significance in a two tailed test = 2.33
By substituting the parameters we have that
For upper tailed
u = 15.8 + 2.33 × (1.8/√872)
u = 15.8 + 2.33 (0.6096)
u = 15.8 + 1.4203
u = 17.2
For lower tailed
u = 15.8 - 2.33 × (1.8/√872)
u = 15.8 - 2.33 (0.6096)
u = 15.8 - 1.4203
u = 14.4
Hence the 98% confidence interval for population mean usage of electricity is (14.4kwh, 17.2kwh)
Answer:
You need to find the surface area.
Answer:
Reciprocal
Step-by-step explanation:
meaning the fraction flipped
Answer:
P = (2,-4)
Q = (3,9)
R = (-4,2)
Step-by-step explanation:
rotation by 180 degrees means that the points are inverted. the answers would be the opposite of the given