A class of 12 students has taken an exam, and the mean of their scores is 71. One student takes the exam late, and scores 92. After including the new score, what is the mean score for all 13 exams?
(12*71 + 92)/13 = 72 8/13
Note that 92 = 71 + 13+8
To find the new mean score after including the late student's score, we will sum up all the scores and divide by the total number of exams.
Step 1: Calculate the sum of the initial 12 scores.
12 students have taken the exam, and the mean score is 71.
Sum of the initial 12 scores = 12 * 71
Step 2: Calculate the total sum after adding the late student's score.
Total sum after adding the late student's score = Sum of the initial 12 scores + Late student's score
Step 3: Calculate the new mean score.
New mean score = Total sum after adding the late student's score / Total number of exams
Let's calculate it:
Step 1: Sum of the initial 12 scores = 12 * 71 = 852
Step 2: Total sum after adding the late student's score = 852 + 92 = 944
Step 3: New mean score = 944 / 13 = 72.62
Therefore, the mean score for all 13 exams, including the late student's score, is 72.62.
To find the mean score for all 13 exams, you need to calculate the sum of all the scores and divide it by the number of exams.
First, you have the sum of the initial 12 scores:
Sum of scores = 12 * 71
To include the new score, you add it to the sum of scores:
Sum of scores = (12 * 71) + 92
Next, you calculate the mean score by dividing the sum of scores by the total number of exams:
Mean score = Sum of scores / Number of exams
In this case, the number of exams is 13, so:
Mean score = (12 * 71 + 92) / 13
Now you can solve this equation to find the mean score for all 13 exams.