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JavaScript

Tadjiev Codes
Tadjiev Codes
9,626 Points
Posted by Tadjiev Codes
Tadjiev Codes
9,626 Points

Can someone explain why I can't get the average number from the array?

```1.Declaring an array with number let numberArrays = [10, 58, 47, 12, 5, 4, 8, -7, 521, -99]; let totalNumber = 10 + 58 + 47 + 12 + 5 + 4 + 8 + -7 + 521 + 99; //2.Print the array and its length. outputElement.innerHTML += numberArrays.length;

    //3.Find and output the average of the array.

    function findAverage(a, b) {
        //totalNumber = a;
        return a / b;
    }
    var averageNum = findAverage(totalNumber, numberArrays.length);
    outputElement.innerHTML += Math.round(averageNum);

The normal function

function findAverage(a, b) { //totalNumber = a; return a / b; } ``` although works if i replace it with numbers. Thanks)))

1 Answer

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,971 Points
KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,971 Points

It looks like for totalNumber you have 99 instead of -99. I added the following to compare sums:

let numberArrays = [10, 58, 47, 12, 5, 4, 8, -7, 521, -99];
let totalNumber = 10 + 58 + 47 + 12 + 5 + 4 + 8 + -7 + 521 + -99; 

console.log(totalNumber)
console.log(numberArrays.reduce((a, b) => a + b, 0))
Tadjiev Codes
Tadjiev Codes
9,626 Points
Tadjiev Codes
Tadjiev Codes
9,626 Points

Thanks) YEs I missed that - 99 . But your code compares it though doesn't output the average number? Thanks in advance)

Tadjiev Codes
Tadjiev Codes
9,626 Points
Tadjiev Codes
Tadjiev Codes
9,626 Points 
var Numbers = [10, 58, 47, 12, 5, 4, 8, -7, 521, -99];


        function printValueWNote(string, value) {

            averageDisplay.innerHTML += string + " : " + value + "<br>";
        }

        function averageOfArray(array) {
            var average = 0;
            var sum = 0;
            for (var index = 0; index < array.length; index++) {
                sum += array[index];
            }
            average = sum / array.length;
            return average;
        }


        printValueWNote("Average", averageOfArray(Numbers));
        printValueWNote("Maximum", Math.max.apply(null, Numbers));
        printValueWNote("Minimum", Math.min.apply(null, Numbers));

I came up with another solution so it generates the average number, max and min numbers from this array. I assume I could do this without the function parameter array I used instead use the totalNumber variable from last code and divide it to the numberArrays.length I mean divide it to the length of the arrays.