If statement in Javascript - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of nested if statements

What is the output of the following code?

Javascript

let x = 10;
if (x > 5) {
  if (x < 15) {
    console.log('A');
  } else {
    console.log('B');
  }
} else {
  console.log('C');
}

A B

B A

C C

D No output

💡 Hint

Check the conditions step by step.

x is 10, which is greater than 5 and less than 15, so the first if and nested if both run, printing 'A'.

❓ Predict Output

intermediate

If statement with else if

What will be logged to the console?

Javascript

let score = 75;
if (score >= 90) {
  console.log('Excellent');
} else if (score >= 70) {
  console.log('Good');
} else {
  console.log('Try again');
}

A Good

B Excellent

C Try again

D No output

💡 Hint

Check which condition matches the score first.

Score is 75, which is not >= 90 but is >= 70, so 'Good' is printed.

❓ Predict Output

advanced

If statement with logical operators

What is the output of this code?

Javascript

let a = 5;
let b = 10;
if (a > 3 && b < 15) {
  console.log('X');
} else if (a > 3 || b > 15) {
  console.log('Y');
} else {
  console.log('Z');
}

A No output

B Z

C X

D Y

💡 Hint

Both conditions in the first if must be true for 'X'.

a is 5 > 3 and b is 10 < 15, so first if condition is true, printing 'X'.

❓ Predict Output

advanced

If statement with type coercion

What will be the output of this code?

Javascript

let val = '0';
if (val) {
  console.log('True');
} else {
  console.log('False');
}

A True

B False

C SyntaxError

D No output

💡 Hint

Check how JavaScript treats non-empty strings in conditions.

Non-empty strings are truthy in JavaScript, so 'True' is printed.

❓ Predict Output

expert

If statement with variable scope

What is the value of x after running this code?

Javascript

let x = 1;
if (true) {
  let x = 2;
  if (true) {
    x = 3;
  }
}
console.log(x);

A 2

B ReferenceError

C 3

D 1

💡 Hint

Consider the scope of variables declared with let inside blocks.

The inner x variables are block scoped and do not affect the outer x, so x remains 1.