how calculate average of 7 highest subjects in javascript code example

Example 1: reduce average javascript

function average(nums) {
  	// nums.length is the important part
    return nums.reduce((a, b) => (a + b)) / nums.length;
}

Example 2: calculate average in javascript

var a = [80, 77, 88, 95, 68];

console.log(eval(a.join('+'))/a.length)