What are negative numbers?
Negative numbers are numbers less than zero. They show things that go below zero — like temperatures below freezing or owing money. We write them with a minus sign, like –3 or –1.
Think of zero as the ground floor. Floors below ground are negative floors.
Number line
Pointer shows current number. Use the buttons to move left (down) or right (up).
Lift (elevator) example — floors below ground are negative
+3
+2
+1
0
-1
-2
0
Imagine the lift starts at the 0 (ground floor). If the lift goes down by 1 floor, it's at −1. If it goes up by 2 floors from −1, it lands at +1.
0
Tip: Adding a negative number is the same as going down. Subtracting a negative is like going up — because you're removing a 'down'.
Child-friendly examples
- Temperature: If it's −3°C outside, it's 3 degrees below zero. The pointer and lift show -3 below the ground floor.
- Money: If you have £5 and spend £8, you have £−3 (you owe £3).
- Lift floors: Basement floors like B1 or −1 are under the ground floor (0).
Try some quick practice
- Start at 0. Add −2. Where are you now?
- Start at −1. Add +3. Where are you now?
- Start at +2. Subtract −4. (Hint: subtracting a negative is adding!)