Has a Pseudo Random number generator, input keys with numerical values as an object into the function and get a uneven random output

randomness.js

function RandomGen(min,max){ // random number
  return Math.round(Math.random()*max-min)+min;
}


function PRandomGen(obj){ // pseudo random number
  // {"thing": 2, "otherthing": 6} // 'otherthing' will be 3x more likely to be returned since 6 is three times 2
  var toReturn, sortable = [], total = 0;

  for(var x in obj){  // loops through all values in the object
    sortable.push([x, obj[x]]); // adds them to the array like: [["thing", 1], ["otherthing", 2]] 
    total += obj[x];  // adds the values of the keys to the total, which will allow for a maximum random number
  }

  sortable.sort(function(a, b) {  // sort the array
    return a[1] - b[1]; // sorts so the smallest are first
  });

  
  var generation = Math.round(Math.random()*total); // generate a number with the maximum we got earlier
  var decide = Math.floor((generation/total)*sortable.length); // this is the actual generation that makes higher numbers more common
  if(decide > sortable.length-1) decide -= 1; // if its larger than the array just make it go down one

  toReturn = sortable[decide][0]; // return the key instead of the value
  return toReturn;
}