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JavaScript JavaScript Array Iteration Methods Array Iteration Practice forEach()

Posted by Peter Huang
Peter Huang
5,427 Points

Can someone provide the answers for this challenge?

what am I missing for my code to get this to work?

app.js 
const numbers = [1,2,3,4,5,6,7,8,9,10];
let times10 = [];

// times10 should be: [10,20,30,40,50,60,70,80,90,100]
// Write your code below

numbers.forEach(total => {
  if( let i = 0; i < numbers.length; i++ ) {
    times10 *= 10;
  }
});

1 Answer

Bella Bradbury
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Bella Bradbury
Front End Web Development Techdegree Graduate 32,790 Points
Bella Bradbury
.a{fill-rule:evenodd;}techdegree seal-36
Bella Bradbury
Front End Web Development Techdegree Graduate 32,790 Points

Hi Peter!

I'm happy to help guide you to a passing answer!

First things first, for each already iterates through the array. You don't need to also add an for loop to access each number. Let's start by taking your multiplication out of the for loop:

numbers.forEach(total => {
  times10 *= 10;
});

From here we need to evaluate what should be multiplied by 10. You currently have it set to times10, the empty array that will hold our results. We need it instead to be the values from the numbers array. You've already defined each number in the original array with the function total. We could keep it like this, but it's kind of a deceiving name. Let's instead go ahead and change both the function name and multiplication variable to number instead:

numbers.forEach(number => {
  number *= 10;
});

Now, let's have another look at the question. It wants us to multiply each number and then add it to the end of the times10 array. To do this we need to use the push() method. Let's add the start of this method:

numbers.forEach(number => {
  number *= 10;
  times10.push();
});

The last step is to define what should be pushed to the times10 array, in this case it's the number value. Adding this we get our final, passing answer:

numbers.forEach(number => {
  number *= 10;
  times10.push(number);
});

Happy coding!

Peter Huang
Peter Huang
5,427 Points

Thank you so much. I really appreciate your time in explaining.