Answer:
C
Step-by-step explanation:
1) The typical sprint time is found by computing the average of the different sprint times, therefore the choice is between option A and C. The average is more accurate when you have a lot of measurements, therefore, since Lamont can run more times in a week than in a day, the correct answer will be:
<span>C) Sprint the 100 meters several times throughout the week and determine his average time to complete from the various runs.
2) T</span><span>he typical amount of energy usage is the average usage for all the neighborhood in one month. Therefore, to calculate the average, you will have to consider the total amount of energy used in a year by all the houses and divide it by the number of months in one year. Therefore, the correct answer will be:
</span><span>B) Take the energy usage of all the homes in the neighborhood for a year, and then divide it by 12.</span>
Answer:
The middle 90% of all freshman biology majors' GPAs lie between 2.31 and 3.43.
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean
and standard deviation
, the z-score of a measure X is given by:
![Z = \frac{X - \mu}{\sigma}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7BX%20-%20%5Cmu%7D%7B%5Csigma%7D)
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 p-value, we get the probability that the value of the measure is greater than X.
Mean 2.87 and standard deviation .34.
This means that ![\mu = 2.87, \sigma = 0.34](https://tex.z-dn.net/?f=%5Cmu%20%3D%202.87%2C%20%5Csigma%20%3D%200.34)
Middle 90% of scores:
Between the 50 - (90/2) = 5th percentile and the 50 + (90/2) = 95th percentile.
5th percentile:
X when Z has a pvalue of 0.05. So X when Z = -1.645.
![Z = \frac{X - \mu}{\sigma}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7BX%20-%20%5Cmu%7D%7B%5Csigma%7D)
![-1.645 = \frac{X - 2.87}{0.34}](https://tex.z-dn.net/?f=-1.645%20%3D%20%5Cfrac%7BX%20-%202.87%7D%7B0.34%7D)
![X - 2.87 = -1.645*0.34](https://tex.z-dn.net/?f=X%20-%202.87%20%3D%20-1.645%2A0.34)
![X = 2.31](https://tex.z-dn.net/?f=X%20%3D%202.31)
95th percentile:
X when Z has a pvalue of 0.95. So X when Z = 1.645.
![Z = \frac{X - \mu}{\sigma}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7BX%20-%20%5Cmu%7D%7B%5Csigma%7D)
![1.645 = \frac{X - 2.87}{0.34}](https://tex.z-dn.net/?f=1.645%20%3D%20%5Cfrac%7BX%20-%202.87%7D%7B0.34%7D)
![X - 2.87 = 1.645*0.34](https://tex.z-dn.net/?f=X%20-%202.87%20%3D%201.645%2A0.34)
![X = 3.43](https://tex.z-dn.net/?f=X%20%3D%203.43)
The middle 90% of all freshman biology majors' GPAs lie between 2.31 and 3.43.
The ratio of the wavelengths of the two notes is 2:1 option fourth 2 to 1 is correct.
<h3>What is wavelength?</h3>
The wavelength is the distance between two successive troughs or crests. The highest point on the wave is the crest, while the lowest point is the trough.
We have two notes
Number of cycle for blue = 8
Number of cycle for red = 4
Ratio = 8:4 = 2:1
Or
2 to 1
Thus, the ratio of the wavelengths of the two notes is 2:1 option fourth 2 to 1 is correct.
Learn more about the wavelength here:
brainly.com/question/7143261
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