Question

a lorry covers the first 30 km. at the speed of 15 km. per hour, the second 30 km at the speed of 20 km. per hours and the last 30 km.at the speed of 25 km. per hour. find the average speed of the lorry

Answer 1

Answer:

Step-by-step explanation:

Avg speed= n÷1/h1+1h2+1/h3+1/h4

Therefore 4÷1/30+1/15+1/30+1/20+1/25 =21.6606

The avg speed of lory is 21.6606