Two Math Teachers

Two mathematics teachers give the same test to each of their classes. The marks for the 30 students in each class are given below.

Compare the data for the two teachers.

• Sort both lists and print them out.
• Find the median (middle value).
• Find quartile 1 (the value 1/4 of the way in)
• Find quartile 3 (the value 3/4 of the way in)
• Find the mean (average).

What does this data tell you about the teachers? Print out your results on the screen.

Some starting code

public class compare
   {
   public static void main (String args [])
   {
   new compare ();
   }

   public compare ()
   {
   int classA [] = {38, 70, 34, 59, 49, 42, 46, 74, 68, 54, 56, 57, 59, 60, 55,    65, 61, 47, 60, 61, 50, 48, 55, 51, 36, 28, 50, 62, 55, 40};
   int classB [] = {60, 78, 85, 58, 70, 55, 68, 79, 81, 68, 48, 59, 64, 74, 88,    81, 82, 80, 69, 77, 76, 78, 72, 73, 65, 64, 90, 53, 73, 80};
   }

   //called like this: bubble(classA) or bubble(classB)
   public void bubble (int a [])
   { //Pre: a is an array with values. It is of size n
   //Post: the values in a are put in ascending order
   int n = a.length;
   int temp;

 for (int i = 0 ; i < n - 1 ; i++)
   {
   for (int j = 0 ; j < n - 1 - i ; j++)
   { // compare the two neighbours
   if (a [j + 1] > a [j])
   { //swap the neighbours if necessary
   temp = a [j];
   a [j] = a [j + 1];
   a [j + 1] = temp;
   }
   }
   }
   }
   }