Modern JavaScript from the Beginning - Second Edition - Array Method Challenges

The video tutorial covers array methods in JavaScript, focusing on filter, map, and reduce functions. It presents three challenges: filtering and mapping an array of people to extract specific data, summing positive numbers from an array, and capitalizing the first letter of words in an array. The tutorial emphasizes understanding these fundamental concepts before moving on to more advanced topics like DOM manipulation.

What is the main goal of the first challenge involving the people array?

• To find the oldest person in the array

• To create a new array with people over 30

• To sort the people by their last names

• To filter people 25 and under and create a new array with their full names and emails

Which array method is used to filter out people older than 25 in the first challenge?

• filter()

• reduce()

• map()

• forEach()

In the first challenge, how are the first and last names combined?

• Using a template string

• Using a regular expression

• Using a loop

• Using concatenation

What is the objective of the second challenge?

• To multiply all the numbers in the array

• To add only the positive numbers in the array

• To sum all the numbers in the array

• To find the largest number in the array

Which method is used to sum the positive numbers in the second challenge?

• forEach()

• reduce()

• map()

• filter()

What is the initial value passed to the reduce method in the second challenge?

• 1

• 0

• The first number in the array

• The last number in the array

What is the task in the third challenge?

• To find the longest word in the array

• To sort the words alphabetically

• To capitalize the first letter of each word in the array

• To reverse the words in the array

Which method is used to capitalize the first letter of each word in the third challenge?

• charAt()

• toUpperCase()

• slice()

• All of the above

How is the rest of the word concatenated after capitalizing the first letter in the third challenge?

• Using the slice method

• Using a regular expression

• Using a loop

• Using a template string

What is the importance of understanding the fundamentals covered in these challenges?

• They are not important

• They help in understanding complex algorithms

• They are crucial for working with the document object model and browser events

• They are only useful for console-based applications