1. To find the sum of two numbers, write a JavaScript function.

The purpose of this question is to gauge the candidate’s foundational knowledge of JavaScript. They evaluate both their problem-solving abilities and comprehension of fundamental syntax. This aids in assessing the candidate’s attention to detail and coding style. 

I would take two parameters and the following function can be used to calculate the sum of any 2 numbers that are passed as arguments. 

function sumOfTwoNumbers(a, b) { 

  return a + b; 

} 

2. Create a JavaScript application that determines an array’s maximum value.

This question is used by a hiring manager to assess a candidate’s capacity for writing understandable and effective code. Candidates must demonstrate error-free code and walk through the code step-by-step. 

function findMaxNumber(arr) { 

  return Math.max(…arr); 

} 

3. To determine whether a given string is a palindrome—one that reads the same way both forward and backward—write a JavaScript function.

The candidate’s knowledge of loop constructions, JavaScript string functions, and other fundamental JavaScript syntax is what the interviewer is searching for. Based on the method employed to answer the palindrome problem, they will assess the candidate’s abilities. 

function isPalindrome(str) { 

  return str === str.split(”).reverse().join(”); 

}

4. To reverse a given string, write a JavaScript program.

Employing managers are looking for a precise response that shows the candidate’s command of JavaScript.  

const reverseString = (str) => str.split(”).reverse().join(”);

5. Create a JavaScript function that accepts a numeric array and outputs a new array containing only even integers.

Interviewers are searching for individuals who can demonstrate the ability to think rationally and clarify their thought processes in addition to being able to clearly describe the solution and the code. 

 By using the filter method on the array, I can check if each element is even or not by using the modulus operator (%) with 2. The element is even if the result is 0. This can be included in the new array. 

function filterEvenNumbers(numbers) { 

  return numbers.filter(num => num % 2 === 0); 

}

6. To find the factorial of a given number, write a JavaScript program.

Managers use this question to gauge a candidate’s grasp of JavaScript programming and algorithmic thinking. The interviewer anticipates that the candidate will show that they understand the factorial notion. 

A factorial number is the product of all positive integers, which are equal to or less than the given number.  

function factorial(number) { 

  if (number === 0 || number === 1) { 

return 1; 

  } else { 

return number * factorial(number – 1); 

  } 

}