Speed, Distance & Time

The Core Formula

Distance = Speed × Time

Rearrange for any unknown:

• Speed = Distance ÷ Time
• Time = Distance ÷ Speed

Tip: cover the unknown in the triangle to read the formula — Distance on top, Speed and Time on the bottom.

Units Must Match

Always convert time to hours when speed is in km/h:

• 30 min = 0.5 h  |  15 min = 0.25 h  |  45 min = 0.75 h  |  90 min = 1.5 h

Worked Examples

Example 1: A car travels at 60 km/h for 2.5 hours. How far?
D = 60 × 2.5 = 150 km

Example 2: A cyclist rides 45 km at 15 km/h. How long?
T = 45 ÷ 15 = 3 hours

Example 3: A runner covers 400 m in 50 seconds. What is their speed?
S = 400 ÷ 50 = 8 m/s

Multi-Stage Journeys & Key Tips

Calculate each leg separately, then add times or distances.

Example: Drive 60 km at 40 km/h, then 60 km at 60 km/h.
T₁ = 60 ÷ 40 = 1.5 h  |  T₂ = 60 ÷ 60 = 1 h  |  Total = 2.5 hours

Key Tips

• Always check that distance, speed, and time units are consistent before calculating
• Average speed = total distance ÷ total time — do NOT average the two speeds directly
• Draw a timeline for complex journeys involving stops or direction changes
• Convert mixed time (e.g., 1 hr 30 min = 1.5 hr) before using the formula