Question

A car travels 80 km at the speed of 20 km/h and the next 30 km at the speed of 30 km/h. What is its average speed?

• A. 20 km/h
• B. 22 km/h
• C. 40 km/h
• D. 30 km/h

Answer 1

Answer:

B. 22 km/h

Average speed = Total distance ÷ Total time

Total distance = 80 + 30 = 110 km

Time taken:
For 80 km at 20 km/h → Time = 80 ÷ 20 = 4 hours
For 30 km at 30 km/h → Time = 30 ÷ 30 = 1 hour

Total time = 4 + 1 = 5 hours

$\text{Average speed} = \frac{110}{5} = 22$

Answer: 22 km/h