Paco's cell phone carrier charges him $0.20 for each text message he sends or receives, $0.15 per minute for calls, and a $15 mo
2 answers:
Answer:
t can be any whole number where 0 ≤ t < 75.
Step-by-step explanation:
Given is:
Paco's cell phone carrier charges him $0.20 for each text message he sends or receives, $0.15 per minute for calls, and a $15 monthly service fee. Paco is trying to keep his bill for the month below $30.
The fixed fee is $15.
So, he has a limit left = $15 for his monthly calls and texts.
That is, the amount he has to pay for texting and calling has to be less than $15.
For texts, Paco is charged $0.20 for sending/receiving texts.
For calls, he is charged $0.15 per minute.
Let 't' represents the number of texts.
Let 'c' represents the number of calls.
Equation forms:
For Paco to send a maximum number of texts, he has to spend 0 minutes on calls.
Substituting c = 0
That is, Paco has to send and receive less than 75 texts.
So, the inequality that best describes the number of texts Paco can send or receive to keep his bill less than $30 in a month is:
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<h3>Answer: 0.061</h3>
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Explanation:
Add up the values to get
1.96+1.81+1.97+1.83+1.87+1.84+1.85+1.94+1.96+1.81+1.86+1.95+1.89= 24.54
Then divide over 13 (the number of values) to get 24.54/13 = 1.8876923 which is approximate.
So the mean is approximately 1.8876923
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Now make a spreadsheet as shown below
We have the first column as the x values, which are the original numbers your teacher provided. The second column is of the form (x-M)^2, where M is the mean we computed earlier. We subtract off the mean and square the result.
After we compute that column of (x-M)^2 values, we add them up to get what is shown in the highlighted yellow cell at the bottom of the column.
That sum is approximately 0.04403076924
Next, we divide that over n-1 = 13-1 = 12
0.04403076924 /12 = 0.00366923077
That is the sample variance. Apply the square root to this to get the sample standard deviation. This is the point estimate of the population standard deviation. As the name implies, it works for samples that estimate population parameters.
sqrt(0.00366923077) = 0.06057417576822
This rounds to 0.061 which is the final answer.