MATHS

I can't seem to understand how to do this question can someone please help? It's 5 marks.

James and Peter cycled along the same 50km route.
James took 2 and 1/2 hours to cycle the 50km.

Peter started to cycle 5 minutes after James started to cycle.
Peter caught up with James when they had both cycled 15km.
James and Peter both cycled at constant speeds.
Work out Peter's speed.

Reply 1

thekidwhogames

Well, James' speed is obviousy 20km/h.

He travelled for 2.5 hours.
Peter started to travel 5 minutes later, which is ... in hours.

We know at distance=15, they caught up to each other. Find an equation and solve.

Reply 2

mistakess

Original post by thekidwhogames

I managed to get James' speed but I don't understand how to put it into a formula.

Reply 3

username3671216

Original post by mistakess

I managed to get James' speed but I don't understand how to put it into a formula.

Use James' speed to work out the time it takes Peter to travel 15km

Reply 4

thekidwhogames

Original post by mistakess

I managed to get James' speed but I don't understand how to put it into a formula.

Well find out the time it took James. Now you know Peter left 5 minutes later so his time will be 5 less minutes (convert to the same units) and then calculate the speed by distance/time.

Reply 5

lydiarutharnold

1. Find James' speed (50/2.5)
2. Find out how long it takes James to travel 15km (time=distance/speed)
3. So James took ___ minutes to travel 15km. Peter will have taken 5 less minutes than this.
4. Speed=d/t so use this to find out Peter's speed. You already have the distance and the time (15 km and the time you worked out in part 3 of this this question).

Because his speed is constant, it's the same no matter what point you measure it from. Once you've followed these 4 steps you should've worked it out.

Hope this helped somewhat :smile:

Reply 6

mistakess

Thank youuuuu it did!

Reply 7

lydiarutharnold

Original post by mistakess

Thank youuuuu it did!

Woooo yesss

Reply 8

alice0502

Is this in a paper your doing as I had it in a mock and would like to be able to see the paper again.

Reply 9

foggy_wigan

So could you please give me the answer so i know if i have got it right?
My tutor has marked up the answer as 22.5k/h but i dont know how he has got this?
Help please

Reply 10

mupsman2312

Original post by foggy_wigan

So could you please give me the answer so i know if i have got it right?
My tutor has marked up the answer as 22.5k/h but i dont know how he has got this?
Help please