code code.js

const collection = [
  { name: 'samundra', rank: 3 },
  { name: 'abina', rank: 5 },
  { name: 'hari', rank: 1 },
  { name: 'bibek', rank: 2 },
  { name: 'suman', rank: 4 },
];

function sortBy(collection, compareBy) {
  return collection.sort((item, lastItem) => {
    return item[compareBy] > lastItem[compareBy];
  });
}

function getAverage(collection, averageBy) {
  return sortBy(collection, averageBy).map(item => item[averageBy])[
    Math.floor(collection.length / 2)
  ];
}

console.log(sortBy(collection, 'rank'));
console.log(getAverage(collection, 'rank'));