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JavaScript JavaScript Array Iteration Methods Combining Array Methods Combining filter() and reduce()

Steven mudie
Steven mudie
5,523 Points

bug in the learning material

Both the reduce and filter methods have not been called yet.

here is my code:

app.js
const purchaseItems = [
    {
        name: 'apples',
        dept: 'groceries',
        price: 2.49
    },
    {
        name: 'bread',
        dept: 'groceries',
        price: 2.99
    },
    {
        name: 'batteries',
        dept: 'electronics',
        price: 5.80
    },
    {
        name: 'eggs',
        dept: 'groceries',
        price: 3.99
    },
    {
        name: 't-shirts',
        dept: 'apparel',
        price: 9.99
    }
];
let groceryTotal;

// groceryTotal should be: 9.47
// Write your code below
groceryTotal = purchaseItems
  .filter(item => item.dept === "groceries")
  .reduce((total,item) => {
    return total += item.price;
  }, 0).toFixed(2);

1 Answer

Steven Parker
Steven Parker
229,788 Points

Apparently, the toFixed is causing the issue by converting the result into a string. It wasn't part of the instructions, and the validator is expecting groceryTotal to be a number.

Steven mudie
Steven mudie
5,523 Points

thanks, removed and it worked..

but the comment says the price should be "9.47" so I prefixed it to 2. Also we learned how to prefix in the previous video in the module so I thought it was necessary.

Steven Parker
Steven Parker
229,788 Points

I can see how that could be confusing. You might drop a note to the Support folks with a suggestion about clarifying the objective.