Sum of all adjacent angles is 180°.
3x + 12 + x = 180
4x + 12 = 180
4x = 168
x = 42°
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Answer: x = 42°
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Since you mentioned the fundamental counting principle, I assume you are looking for the total number of possibilities.
If you are picking a month, there are 12 options.
If you are selecting a day of the week, there are 7 options.
If you are doing both, you multiply the two numbers together.
12 x 7 = 84
Would it be 3.4, 4.3, 5.2, 6.1, 7
The expression that represents the ratio of the difference of the two means to Sidney’s mean absolute deviation is given by: Option B: 4/3.28
<h3>What is mean absolute deviation?</h3>
Mean absolute deviation is the average of the absolute deviation of each observation from their mean, for a considered set of observations.
For this case, the table of mean and mean absolute deviation is given as:

(M.A.D refers to Mean Absolute Deviation).
So, difference in their mean is 82 - 78 = 4
Absolute deviation for Sidney is 3.28
Thier ratio is: 4/3.28
Thus, the expression that represents the ratio of the difference of the two means to Sidney’s mean absolute deviation is given by: Option B: 4/3.28
Learn more about ratio here:
brainly.com/question/12106245