JSFiddle - React, Tailwind, and code Playground

HTML

<div class="response"></div>

TypeScript

function minutesToHour (minutes) {
	let resultMinutes = Math.ceil(minutes % 60);
  let time = Math.floor(minutes / 60) + ':';
  time += resultMinutes < 10 ? '0' + resultMinutes : resultMinutes;
	return time;
}

function hourToMinutes (hour) {
	let hAndM = hour.split(':');
  let h = parseInt(hAndM[0]);
  let m = parseInt(hAndM[1]);
  return h * 60 + m;
}

function getTimeAverage (timeArr: any) {
	let allTime = 0;
  for (let time of timeArr) {
  	allTime += hourToMinutes(time)
  }
  return minutesToHour(allTime / timeArr.length);
}

const t1 = '16:46'
const t2 = '17:04'
const t3 = '17:39'
const t4 = '10:46'
const t5 = '09:03'
const t6 = '11:09'
const t7 = '10:10'
const t8 = '10:05'
const t9 = '17:56'
const t10 = '10:10'
const t11 = '11:03'
const t12 = '09:31'
const t13 = '11:32'
const t14 = '14:35'
const t15 = '10:00'
const t16 = '10:04'
const t17 = '09:44'
const t18 = '09:57'

document.querySelector('.response').innerHTML = getTimeAverage([t1, t2, t3, t4, t5,t6,t7,t8,t9,t10,t11,t12,t13,t14,t15,t16,t17,t18])