The company has to study 199 machines.
In statistics, the standard deviation is a measure of the amount of variation or dispersion of a set of values. A low standard deviation indicates that the values tend to be close to the mean of the set, while a high standard deviation indicates that the values are spread out over a wider range.
It is given that;
Margin of error E = 0.7
Confidence interval 98% = 1-0.98 = 0.02
Standard deviation = 6 hours
Number of MRI machines needed per day n, = [(z alpha/2 * SD)/E]²
Z alpha/2 = 1.645 at alpha = 0.1
Inputting these values into n we have that
[(1.645*6)/0.7]²
= 14.1²
= 198.81 is approximately equal to 199
The company has to study 199 machines.
To know more about standard deviation visit: brainly.com/question/475676
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Answer:</h2>

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Step-by-step explanation:</h2>
A trapezoid is a quadrilateral where at least one pair of opposite sides are parallel. In a trapezoid, the both parallel sides are known as the bases of the trapezoid. So we have two bases, namely,
. Also, the height
of the trapezoid is the length between these two bases that's perpendicular to both sides. So the area of a trapezoid in terms of of
is:

Since:

The area is:

Answer:
100%
Step-by-step explanation:
Use conditional probability:
P(B | A) = P(B and A) / P(A)
P(B | A) = (12/28) / P(A)
We need to find the probability that a student studies art.
P(A or B) = P(A) + P(B) − P(A and B)
24/28 = P(A) + (12+12)/28 − 12/28
P(A) = 12/28
P(B | A) = (12/28) / (12/28)
P(B | A) = 1
What this means is that all of the students who study art also study biology.
30+6+0.4+0.09+0.005=36.495
Answer: The probability in (b) has higher probability than the probability in (a).
Explanation:
Since we're computing for the probability of the sample mean, we consider the z-score and the standard deviation of the sampling distribution. Recall that the standard deviation of the sampling distribution approximately the quotient of the population standard deviation and the square root of the sample size.
So, if the sample size higher, the standard deviation of the sampling distribution is lower. Since the sample size in (b) is higher, the standard deviation of the sampling distribution in (b) is lower.
Moreover, since the mean of the sampling distribution is the same as the population mean, the lower the standard deviation, the wider the range of z-scores. Because the standard deviation in (b) is lower, it has a wider range of z-scores.
Note that in a normal distribution, if the probability has wider range of z-scores, it has a higher probability. Therefore, the probability in (b) has higher probability than the probability in (a) because it has wider range of z-scores than the probability in (a).