Answer:
2119 students use the computer for more than 40 minutes. This number is higher than the threshold estabilished of 2000, so yes, the computer center should purchase the new computers.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:

The first step to solve this question is finding the proportion of students which use the computer more than 40 minutes, which is 1 subtracted by the pvalue of Z when X = 40. So



has a pvalue of 0.7881.
1 - 0.7881 = 0.2119
So 21.19% of the students use the computer for longer than 40 minutes.
Out of 10000
0.2119*10000 = 2119
2119 students use the computer for more than 40 minutes. This number is higher than the threshold estabilished of 2000, so yes, the computer center should purchase the new computers.
The unit price is 90 cents per can of tomato sauce.
Answer:
Look at explanation.
Step-by-step explanation:
For the first four, take the first term and add the common difference to it to get the second term. Then add the common difference to the second term to get the third term, and so on until the 5th term. If the common difference is negative, you subtract it instead of adding it.
The total money Dana spent in all is $24.75
<h3>Ratio and proportions</h3>
Ratio are written as fractions of two integers. For instance a/b.
Amount spent for grandmother = $13.75
Amount spent on grand father = 4/5 * 13.75
Amount spent on grand father = $11
Take the sum
Total money spent = $13.75 + $11
Total money spent = $24.75
Hence the total money Dana spent in all is $24.75
Learn more on proportion here: brainly.com/question/19994681
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