Answer: (29.4, 32.6)
Step-by-step explanation:
From the question, we know that
Sample size (n) = 27
Sample mean (x) = $31
Sample standard deviation (s) = $3
We are to construct a 99% confidence interval interval for average amount spent on gift.
The formulae for constructing a 99% confidence interval for population mean is given as
u = x + tα/2 × s/√n...... For upper limit
u = x - tα/2 × s/√n...... For lower limit
tα/2 is the critical value for a 2 tailed test. This value of gotten from a t distribution table by checking the degree of freedom ( 27 - 1 = 26) against the level of significance ( 100% - 99% = 1%).
Hence tα/2 = 2.779
Let us substitute our parameters and solve
For lower limit
u = 31 - 2.779 × 3/√27
u = 31 - 2.779 ( 0.5773)
u = 31 - 1.6045
u = 29.4
For upper limit
u = 31 + 2.779 × 3/√27
u = 31 + 2.779 ( 0.5773)
u = 31 + 1.6045
u = 32.6
Hence the 99% confidence interval for population mean is given as 29.4, 32.6
Answer:
nope. sorry man the answer for 864 - 45 = 819
Step-by-step explanation:
Answer:
P (A and B)=8/9
Events A and B are not dependent.
Step-by-step explanation:
Probability of A AND B means the the probability (favorable outcomes divided by total) of choosing someone who has/did BOTH A and B (not neither or only one of them). 16 did both, so the probability is 16/18 /2/2 = 8/9.
The events are independent (not dependent) because choosing A does not affect choosing B.
B. 1,147, I’m not quite sure
