Difference in the number of laps covered by two runners with different speeds

125 Views Asked by At

Stuck on this question for my 9-year old (no calculator allowed) - the section the teacher gave was in LCM and HCF - I think it is LCM to be used in this query? The LCM she worked out as 1200 but is now stuck on the next steps on this..any help please..

I thought Ellen would be 1200/48 = 25 and then work out Matthew: 1200/100 = 120 - so the difference would be 95 laps - is this the right answer? Plus, don't think this is using LCM/HCF?

Ellen and Matthew entered a race around a track starting from the same point. Ellen takes 48 seconds and Matthew takes 100 seconds to run a lap. If they keep their paces, how many more laps would Ellen complete compared to Matthew after 1200 seconds?

1

There are 1 best solutions below

0
On

Mathew will run $12$ laps, not $120$. So the difference will be $25-12=13$ laps.