Question

In a class of 25 students, 24 of them took an exam in class and 1 student took a make-up exam the following day. The professor graded the first batch of 24 exams and found an average score of 74 points with a standard deviation of 8.9 points. The student who took the make-up the following day scored 64 points on the exam. what is the new average

Answer 1

Answer:

The  value is   $\mu_n = 73.6$

Step-by-step explanation:

From the question we are told that

   The total number of students is  $N = 25$

    The  number of student that took exam in class is  n  = 24

    The number that took make up exam is  k  =  1

     The  average score of the first 24 students is  $\mu = 74$

       The  standard deviation is $\sigma = 8.9$

      The  average score of the student who took make up test is $\= x = 64$

Generally the new average is mathematically represented as

      $\mu_n = \frac{( n * \mu ) + \= x }{N}$

      $\mu_n = \frac{( 24 * 74 ) + 64 }{25}$

       $\mu_n = 73.6$