If Ying Zyiyu covered the first 200 miles of a trip going at 50 mph and the last hundred miles going at 40 mph, what was his average speed for the entire trip?

Question

I do not unsterstand how to do this. Please help someone

Answer 1

Hello,

 

In order to solve this problem, we need to know the duration the Ting traveled at each speed, then we can find the average speed. This can be divided into two parts:

 

Part 1. Find the duration traveled at each speed

Ting covered 200 miles at 50 miles/hour

To find duration traveled at 50mph --> (200 miles)/(50mph) = 4 hours (traveling at 50 mph)

 

Ting traveled 100 miles at 40 mph

To find duration traveling at 40mph --> (100 miles)/(40mpg) = 2.5 hours (traveling at 40mph)

 

Part 2. Find average speed

Average speed = total distance/total time

(200 miles + 100 miles)/(4hours + 2.5hours) = 46.2 mph is the average speed