To find out the number of prescriptions filled during hour 2, we follow these steps:
1. Identify the Known Information:
- Total number of hours (data points): [tex]\( 8 \)[/tex]
- Known number of prescriptions for hours: [tex]\[ 18, ?, 22, 25, 16, 24, 22, 28 \][/tex]
- Mean number of prescriptions: [tex]\( 21 \)[/tex]
2. Calculate the Total Prescriptions Target:
The mean is given as 21. The mean formula is:
[tex]\[
\text{mean} = \frac{\text{total number of prescriptions}}{\text{total number of hours}}
\][/tex]
We rearrange this to find the total number of prescriptions:
[tex]\[
\text{total number of prescriptions} = \text{mean} \times \text{total number of hours}
\][/tex]
Plugging in the values:
[tex]\[
\text{total number of prescriptions} = 21 \times 8 = 168
\][/tex]
3. Sum the Known Numbers of Prescriptions:
Adding the known prescriptions:
[tex]\[
18 + 22 + 25 + 16 + 24 + 22 + 28 = 155
\][/tex]
4. Calculate the Missing Value:
The missing value (number of prescriptions filled during hour 2) can be found by subtracting the sum of the known prescriptions from the total prescriptions target:
[tex]\[
\text{missing prescriptions} = 168 - 155 = 13
\][/tex]
Therefore, the number of prescriptions filled during hour 2 is:
A. 13
