Uunderstanding Undefined Value returned from a Function

Tell us what’s happening:
add 5 to the sum variable, I don’t get this point, could anyone help me? please

Your code so far


// Example
var sum = 0;
function addThree() {
  sum = sum + 3;
}

// Only change code below this line
var sum = 8;
function addFive (){
  sum = 5 + 3;
}


// Only change code above this line
var returnedValue = addFive();

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Link to the challenge:
https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-javascript/understanding-undefined-value-returned-from-a-function

it means set sum to 8, it doesn’t mean you add 5 to current value. check the addThree, it adds 3 to existing sum value as sum = sum + 3 ; means sum is equal to sum add with 3

now fix the five

keep goin on great work, happy programming