Question

Andy drives 65 km at an average speed of 110 km/h and then 5 km at 60 km/h without stopping. What is the average speed for the whole journey to 1 dp?

Answer 1

Answer: 103.8 km/h

Formula = Speed × Time = Distance

Time taken for first part of journey = 65 ÷ 110

= 13/22 hours

Time taken for second part of journey = 5 ÷ 60

= 1/12 hours

Avg speed = Total distance travelled ÷ Total time taken

= (65 + 5) ÷ [(13/12) + (1/12)]

= 103.8 km/h (to 1 dp)