Logical operators in Javascript - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if both conditions are true.

Javascript

if (a > 5 [1] b < 10) {
  console.log('Both conditions are true');
}

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

A&

B||

C&&

D!

Attempts:

3 left

💡 Hint

Common Mistakes

Using || instead of && will check if either condition is true.

Using & is a bitwise operator, not logical.

Using ! negates a condition, not combines two.

The logical AND operator (&&) checks if both conditions are true.

2fill in blank

medium

Complete the code to check if at least one condition is true.

Javascript

if (x === 0 [1] y === 0) {
  console.log('At least one is zero');
}

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

A&

B||

C!

D&&

Attempts:

3 left

💡 Hint

Common Mistakes

Using && requires both conditions to be true, not one.

Using & is a bitwise operator, not logical.

Using ! negates a condition, not combines two.

The logical OR operator (||) checks if at least one condition is true.

3fill in blank

hard

Fix the error in the condition to correctly negate the expression.

Javascript

if (! (a === 10 [1] b === 20)) {
  console.log('Condition is false');
}

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

A||

B!

C&&

D&

Attempts:

3 left

💡 Hint

Common Mistakes

Using && inside negation changes the logic incorrectly.

Using & is a bitwise operator, not logical.

Using ! inside the parentheses is redundant.

The negation applies to the OR condition, so || is correct inside the parentheses.

4fill in blank

hard

Fill both blanks to create a condition that checks if number is between 5 and 15 inclusive.

Javascript

if (number [1] 5 [2] number [3] 15) {
  console.log('Number is between 5 and 15');
}

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

A>=

B<

C&&

D||

Attempts:

3 left

💡 Hint

Common Mistakes

Using || instead of && will allow numbers outside the range.

Using > instead of >= excludes 5.

Using <= instead of < includes 15, which may be incorrect.

The condition uses >= 5 AND < 15 to check the range.

5fill in blank

hard

Fill all three blanks to create a condition that logs if a string is empty or null.

Javascript

if (str [1] null [2] str [3] '') {
  console.log('String is empty or null');
}

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

A===

B||

D&&

Attempts:

3 left

💡 Hint

Common Mistakes

Using && will require both conditions to be true, which is impossible.

Using == instead of === can cause unexpected type coercion.

Using & is a bitwise operator, not logical.

The condition checks if str is null OR equals empty string using === and ||.