The confidence interval formula is computed by:
Xbar ± Z s/ sqrt (n)
Where:
Xbar is the mean
Z is the z value
S is the standard deviation
N is the number of samples
So our given are:
90% confidence interval with a z value of 1.645
Sample size 40, 45
Mean 180, 179
Standard deviation 2, 4
So plugging that information in the data will give us a
confidence interval:
For 1:
Xbar ± Z s/ sqrt (n)
= 180 ± 1.645 (2 / sqrt (40))
= 180 ± 1.645 (0.316227766)
= 180 ± 0.520194675
= 179.48, 180.52
For 2:
Xbar ± Z s/ sqrt (n)
= 179 ± 1.645 (4 / sqrt (45))
<span>= 179 ± 1.645 (0.596284794)</span>
therefore, the answer is letter b
Answer: 15 and one-half
Step-by-step explanation:
14/2 + 3(4) - (6.5 - 3)
Use PEMDAS
14/2 + 3(4) - 3.5
Use PEMDAS
7 + 12 - 3.5
Use PEMDAS
15.5
You say you’re going to the police
7.85 dollars because 3.14 is the price of one pound your buying 2.5 so you times 3.14 by 2.5