return an average from array in javascript code example

Example 1: how to calculate average of array in javascript

const arrAvg = arr => arr.reduce((a,b) => a + b, 0) / arr.length

Example 2: getting average of array javascript

var total = 0;
for(var i = 0; i < grades.length; i++) {
    total += grades[i];
}
var avg = total / grades.length;