Calculate floor-of-9.99

Round numbers, floor, ceiling — step by step.

Number

Answer

-10

To find the floor of -9.99, follow the step-by-step solution below.

Step 1 — Apply the floor function

The floor function rounds down (toward negative infinity) to the largest integer less than or equal to the number.

-9.99 lies between -10 and -9. The largest integer ≤ -9.99 is -10.

Note: for negative numbers, the floor goes further from zero, not toward zero.

⌊-9.99⌋ = -10

Floor-of-9.99: look at the digit after the rounding position to decide whether to round up or down.

This is a Rounding — rounding operation

What is the answer to floor-of-9.99?
The answer is -10.

What method is used?
Round up if the next digit is 5 or more, round down if less than 5. Floor always rounds down, ceiling always rounds up.