JS Practice — Built-in Objects

Math.floor() Leaves Integers Unchanged

📖 Usage Example

// Round down to the nearest integer
Math.floor(4.9)   // → 4
Math.floor(-4.1)  // → -5

Use Math.floor() when you need to round a number down to the nearest whole integer.

Math.floor(x)

When the input is already an integer, Math.floor() returns it unchanged. Math.floor(4) returns 4.

Challenge: Verify that Math.floor() is idempotent for integers.

💡 Hints (2)