Final answer:
To find the mean, add up all the numbers and divide by the total number of numbers. The mean of 57.75 represents the average number of students who left school early per day. The impact on the mean of adding another teacher with an age of 45 is unclear without the full list of ages.
Step-by-step explanation:
To find the mean of a set of numbers, you add up all the numbers and then divide by the total number of numbers.
In this case, the numbers represent the number of students who left school early in a 12-day period.
So, you add up the numbers: 48 + 62 + 75 + 43 + 32 + 52 + 70 + 63 + 81 + 40 + 38 + 67 = 693.
Then, divide by the total number of numbers, which is 12. So, the mean is 693 ÷ 12 = 57.75.
The mean represents the average number of students who left school early in a 12-day period.
In this case, the mean of 57.75 means that, on average, about 57 to 58 students left school early each day over the 12-day period.
If another teacher with an age of 45 is added to the list, the mean would be impacted.
To find the new mean, you would add up all the ages, including the age of 45, and then divide by the total number of ages.
However, since we do not have the full list of ages for the teachers, we cannot calculate the new mean.