<h3>
Answer: 6</h3>
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Explanation:
Think of a table that has 2 rows and 3 columns.
Each row represents a different math class (either Algebra or Geometry).
Each column represents a different foreign language class (French, Spanish or Latin).
This table has 2*3 = 6 cells inside. Each cell represents a different combination of classes possible.
In short, all we have to do is multiply the number of classes for each subject.
Answer:
fourth option... ...dmdmdjxn
It costs 5,5! Bc 1 costs 0,5
Answer:
0.82% probability that the average time it takes to complete both homework assignments is greater than 82 minutes
Step-by-step explanation:
When the distribution is normal, we use the z-score formula.
In a set with mean
and standard deviation
, the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
Math homework:
![\mu_M = 30, \sigma_M = 3](https://tex.z-dn.net/?f=%5Cmu_M%20%3D%2030%2C%20%5Csigma_M%20%3D%203)
Arts homework:
![\mu_A = 40, \sigma_A = 4](https://tex.z-dn.net/?f=%5Cmu_A%20%3D%2040%2C%20%5Csigma_A%20%3D%204)
What is the probability that the average time it takes to complete both homework assignments is greater than 82 minutes?
Here, we have a sum of normal variables. The mean will be the sum of the means, while the standard deviation is the square root of the sum of the variances. So
![\mu = \mu_M + \mu_A = 30 + 40 = 70](https://tex.z-dn.net/?f=%5Cmu%20%3D%20%5Cmu_M%20%2B%20%5Cmu_A%20%3D%2030%20%2B%2040%20%3D%2070)
![\sigma = \sqrt{\sigma_M^2 + \sigma_A^2} = \sqrt{3^2+4^2} = 5](https://tex.z-dn.net/?f=%5Csigma%20%3D%20%5Csqrt%7B%5Csigma_M%5E2%20%2B%20%5Csigma_A%5E2%7D%20%3D%20%5Csqrt%7B3%5E2%2B4%5E2%7D%20%3D%205)
This probability is 1 subtracted by the pvalue of Z when X = 82. So
![Z = \frac{X - \mu}{\sigma}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7BX%20-%20%5Cmu%7D%7B%5Csigma%7D)
![Z = \frac{82 - 70}{5}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7B82%20-%2070%7D%7B5%7D)
![Z = 2.4](https://tex.z-dn.net/?f=Z%20%3D%202.4)
has a pvalue of 0.9918
1 - 0.9918 = 0.0082
0.82% probability that the average time it takes to complete both homework assignments is greater than 82 minutes