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JavaScript JavaScript Array Iteration Methods Array Manipulation Practice reduce()


How can I complete this task ? Thanks!

const phoneNumbers = ["(503) 123-4567", "(646) 123-4567", "(503) 987-6543", "(503) 234-5678", "(212) 123-4567", "(416) 123-4567"];
let numberOf503;

// numberOf503 should be: 3
// Write your code below
numberOf503 = phoneNumbers.reduce( number => {
  if(number === charAt(503){
        return numberOf503;

Reggie Williams
Reggie Williams
Treehouse Teacher

Hey Azzie Fuzzie the charAt method will return the characters at a given index. It looks like you're attempting to check if the numbers start with 503 using the charAt() method. Try instead using a method like substring then inside your return statement, make sure you return number instead of numberOf503

1 Answer