title: The operator + is undefined for the argument type(s) java.util.Scanner
body: <p>How to remove this error ? please anyone help
  I'm getting an error "The operator + is undefined for the argument type(s) java.util.Scanner"
  don't know why is it showing this?   </p>
  
  <p>package com.learn.java;</p>
  
  <pre><code>import java.util.Scanner;
  
  public class GradeCalculator {
  
      public static void main(String[] args) {
  
          System.out.println("Enter marks of MATHS");
          Scanner math = new Scanner(System.in);
          System.out.println(math.nextFloat());
  
          System.out.println("Enter marks of ENGLISH");
          Scanner eng = new Scanner(System.in);
          System.out.println(eng.nextFloat());
  
          System.out.println("Enter marks of SOCIALSCIENCES");
          Scanner socialScience = new Scanner(System.in);
          System.out.println(socialScience.nextFloat());
  
          System.out.println("Enter marks of SCIENCE");
          Scanner science = new Scanner(System.in);
          System.out.println(science.nextFloat());
  
          float avgMarks = averageCalculator(math, eng, socialScience, science);
          System.out.println(avgMarks);
          calculatePerformanceGrades(avgMarks);
  
      }
  
      private static float averageCalculator(Scanner math, Scanner eng,
              Scanner socialScience, Scanner science) {
          float averageMarks;
          averageMarks=((math + eng + socialScience + science) / 4);//getting an error here(The operator + is undefined for the argument type(s) java.util.Scanner)
          return averageMarks;
  
      }
  
      private static void calculatePerformanceGrades(float avgMarks) {
          if (avgMarks &lt; 40) {
              System.out.println("Poor");
          } else if (avgMarks &gt;= 40 &amp;&amp; avgMarks &lt; 59) {
              System.out.println("Average");
          } else if (avgMarks &gt;= 60 &amp;&amp; avgMarks &lt; 79) {
              System.out.println("Good");
          } else if (avgMarks &gt;= 80 &amp;&amp; avgMarks &lt; 89) {
              System.out.println("Very Good ");
          } else if (avgMarks &gt;= 90 &amp;&amp; avgMarks &lt;= 100) {
              System.out.println("Excellent");
          }
      }
  }
  </code></pre>
  
  <p>Please help to solve the issue.</p>