Find and some methods in Javascript - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to find the first number greater than 10 in the array.

Javascript

const numbers = [4, 9, 15, 7];
const result = numbers.[1](num => num > 10);

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Afilter

Bfind

Cmap

Dreduce

Attempts:

3 left

💡 Hint

Common Mistakes

Using filter returns an array, not a single element.

Using map transforms all elements, not find one.

The find method returns the first element that satisfies the condition.

2fill in blank

medium

Complete the code to check if some numbers in the array are even.

Javascript

const numbers = [1, 3, 5, 6];
const hasEven = numbers.[1](num => num % 2 === 0);

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Aevery

Bfind

Cfilter

Dsome

Attempts:

3 left

💡 Hint

Common Mistakes

Using every checks all elements, not some.

Using find returns the element, not a boolean.

The some method returns true if at least one element meets the condition.

3fill in blank

hard

Fix the error in the code to find the first string longer than 3 characters.

Javascript

const words = ['cat', 'dog', 'bird'];
const longWord = words.[1](word => word.length > 3);

Drag options to blanks, or click blank then click option'

Afind

Bsome

Cfilter

Dmap

Attempts:

3 left

💡 Hint

Common Mistakes

Using some returns a boolean, not the element.

Using filter returns an array of all matches.

find returns the first element matching the condition, which is what we want here.

4fill in blank

hard

Fill both blanks to create an array of words longer than 4 characters using filter and check if some words start with 'a'.

Javascript

const words = ['apple', 'bat', 'anchor', 'cat'];
const longWords = words.[1](word => word.length > 4);
const hasAStart = words.[2](word => word.startsWith('a'));

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Afilter

Bfind

Csome

Dmap

Attempts:

3 left

💡 Hint

Common Mistakes

Using find instead of filter returns only one word.

Using map does not filter or check conditions.

filter creates a new array with words longer than 4 characters.
some checks if any word starts with 'a'.

5fill in blank

hard

Fill all three blanks to find the first number divisible by 3, check if some numbers are negative, and filter numbers greater than 5.

Javascript

const nums = [2, -3, 6, 8];
const firstDiv3 = nums.[1](num => num % 3 === 0);
const hasNegative = nums.[2](num => num < 0);
const greaterThan5 = nums.[3](num => num > 5);

Drag options to blanks, or click blank then click option'

Afilter

Bsome

Cfind

Devery

Attempts:

3 left

💡 Hint

Common Mistakes

Using every instead of some for checking negatives.

Using map instead of filter for filtering numbers.

find returns the first number divisible by 3.
some checks if any number is negative.
filter creates an array of numbers greater than 5.