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:
Step-by-step explanation:
we know that
The volume of a trough is equal to
where
B is the area of equilateral triangle
L is the length of a trough
step 1
Find the area of equilateral triangle B
The area of a equilateral triangle applying the law of sines is equal to
where
substitute
step 2
Find the volume of a trough
we have
substitute
Answer:
2700.
Step-by-step explanation:
The total distance would be 2700.
Distance traveled between in 6th second and 12th second is 2430-2160=270 meter. That means Superman covered 270 meter in 6 seconds.
So, now if he is moving at the same speed, he should cover the same distance in first 6 seconds which is 270 meter.
Suppose the whole distance is X when time is 0, and after flying for 6 seconds he now is 2430 meter away. It means that he must have covered the distance of X-2430=270.
Finding for X, we gets the full initial distance, when time was 0.
The simple trick is, once we get the distance he has covered in 6 seconds, we can form the equation like subtracting the whole distance- remaining distance equals to covered distance.
Answer
1st is yes
2nd is no
Step-by-step explanation:
