Question

So, I have two arrays: grade[] and grade2[] that contains elements I give from windows.prompt . I want to add a value from grade with a value from grade2 so i can calculate “media”. But the code that i wrote just concats those two values, doesn’t add them actually. I am a beginner and I hope you can help me. Thank you!

function display_student() 
{ 
 var n=window.prompt("Number of students: "+"");
 var name= new Array(n);
 var grade=new Array(n); 
 var grade2=new Array(n); 
 var y=0; 
 for (y=0; y<n; y++) 
 { 
name[y]=window.prompt("Student name:","");
grade[y]=window.prompt("Grade 1: ","5");
grade2[y]=window.prompt("Grade 2: ","5")

document.write("</br>"+"Student name: "+name[y]+"</br>"+"Grade 1: "+grade[y]+"    </br>"+"Grade 2: "+grade2[y]+"</br>");
var media=(grade[y]+grade2[y])/2;

document.write("Media: "+media+"</br>");
if(media<5)
document.write("Failed");
else
document.write("Promoted");
  } 
}    

Answer 1

Use the parseInt function before adding.

var media=(parseInt(grade[y]) + parseInt(grade2[y]))/2;