Question

Tony completed a 720 km journey with an average speed of 90 km/h for the first 285 km he travelled at an average speed of 95 Km/h what was the average speed for the remaining journey

Answer 1

Answer:

$Speed = 87 km/h$

Explanation:

Given

Total Distance = 720km

Average Speed = 90km/h

Average Speed (285km) = 95km/h

Required

Determine the average speed for the rest of the journey

First we need to determine the time taken to complete the journey using

$Speed = \frac{Distance}{Time}$

$90 = \frac{720}{Time_1}$

Make Time the subject of formula

$Time_1 = \frac{720}{90}$

$Time_1 = 8 hour$

Next, we determine the time taken to complete 285km of the journey using

$Speed = \frac{Distance}{Time}$

$95 = \frac{285}{Time_2}$

Make Time the subject of formula

$Time_2 = \frac{285}{95}$

$Time_2 = 3 hours$

The difference between these calculated times is the time taken to complete the rest of the journey

$Time = Time_1 - Time_2$

$Time = 8\ hour - 3\ hour$

$Time = 5\ hour$

Also, we need to calculate the distance of the rest of the journey

$Distance = 720\ km - 285\ km$

$Distance = 435\ km$

The average speed can then be calculated;

$Speed = \frac{Distance}{Time}$

$Speed = \frac{435}{5}$

$Speed = 87 km/h$

Hence, the average speed of the rest of the journey is 87km/h