You are here:

- Home
- Science
- Mathematics
- Advanced Math
- Average Speed question

Advertisement

Salam.

I have a Speed/Distance/Time question for IGCSE. The question is: A car travels for 60 km at 30 km/h and then a further 180 km at 160 km/h.

(a)Find the total time taken

(b)Find the average speed for the whole journey.

Thank you in advance.

Hi Hanaa,

a) We know that Speed = Distance / Time

So, Time = Distance / Speed

When the car travels 60km at 30km/h it takes a time of

60/30 = 2 hours

and when it travels 180km at 160km/h it takes a time of

180/160 = 1.125 hours

The total time taken is therefore 2 + 1.125 = 3.125 hours

Note that if you so require you can convert the decimal part into minutes by multiplying by 60.

0.125 hours = 0.125 x 60 mins = 7.5 minutes

and the total time is 3 hours and 7.5 minutes.

b) The total distance covered = 60km + 180km = 240km

The total time taken = 3.125 hours

Average Speed = Total Distance / Total Time

= 240 / 3.125

= 76.8 km/h

Regards

Advanced Math

Answers by Expert:

I can provide good answers to questions dealing in almost all of mathematics especially from A`Level downwards. I can as well help a good deal in Physics with most emphasis directed towards mechanics.

Aspiring theoretical physicist. I have been doing maths and physics all my life.**Education/Credentials**

I teach mathematics and engineering physics.