This discussion is now closed.
Check out other Related discussions
- Edexcel GCSE Mathematics Paper 1 Foundation (1MA1 1F) - 16th May 2024 [Exam Chat]
- Edexcel GCSE Foundation tier Maths Paper 3 3F (1MA1) - 14th June 2023 [Exam Chat]
- Muslim/general advice in maths💗
- Need help on maths foundation question Gcse
- help pls-urgent maths question!
- SOS medical microbiology research
- Studying abroad after access course?
- A-Level Choices
- KCL v Exeter - Pros v Cons PLEASE
- How to maintain focus, for real
- what do I take for A Level?
- LAE or LSC?
- Is there any video-based A Level course?
- Masters Degree After Several Years out - Worth it?
- GCSE Mathematics Study Group 2024-25
- WJEC GCSE Mathematics Unit 1 Higher (3300U50-1) - 16th May 2024 [Exam Chat]
- Pls can someone mark my AQA English Language paper 1? Thank you in advance!
- Advice as a muslim
- southampton uni accom 24/25
- Physics Students: At what age did you loose your virginity?
Stuck on a supposedly a LCM question
City Hoppa runs two buses starting from the same bus-stop
One bus has a route that takes 20 minutes
The other bus has a route that takes 55 minutes
Both buses leave the bus-stop at 6 a.m. and run continuously
What is the next time that the buses will be at the stop together?
answer = .....a.m.
Tried working out the LCM but didnt work...how do I do it?
One bus has a route that takes 20 minutes
The other bus has a route that takes 55 minutes
Both buses leave the bus-stop at 6 a.m. and run continuously
What is the next time that the buses will be at the stop together?
answer = .....a.m.
Tried working out the LCM but didnt work...how do I do it?
Reply 1
krussel
Tried working out the LCM but didnt work...how do I do it?
Tried working out the LCM but didnt work...how do I do it?
Technique sounds right. I get 9:40 a.m.
krussel
...
yeah i get 9.40am too, with the LCM of 220.
i think theres a nice way to calculate LCM if i can remember it correctly...
-list the prime factors of both numbers: 2,2,5 5,11
-remove any repeats: 2,2,5,11
-multiply: 220
i think that works (please correct me if i am wrong someone).
Reply 3
dont see how u got that because the lcm is 220 of 55 and 20
Reply 4
krussel
dont see how u got that because the lcm is 220 of 55 and 20
220 minutes = 3 hrs 40 min. which you then add on to the 6 a.m. start time to get 9:40.
Reply 5
ohhh i see okay thanks 
Reply 6
Lou Reed
yeah i get 9.40am too, with the LCM of 220.
i think theres a nice way to calculate LCM if i can remember it correctly...
-list the prime factors of both numbers: 2,2,5 5,11
-remove any repeats: 2,2,5,11
-multiply: 220
i think that works (please correct me if i am wrong someone).
i think theres a nice way to calculate LCM if i can remember it correctly...
-list the prime factors of both numbers: 2,2,5 5,11
-remove any repeats: 2,2,5,11
-multiply: 220
i think that works (please correct me if i am wrong someone).
Let (a,b) denote the GCD of a and b.
Let [a,b] denote the LCM of a and b.
Using the Euclidean Algorithm we can show;
ab = [a,b](a,b) - a far nicer way imho - factoring is hard
Reply 7
I tried you time theory on my maths (the website) and it said it was not 9:40 but instead 9:45 but you were very close!
Original post by FamilyFlags
I tried you time theory on my maths (the website) and it said it was not 9:40 but instead 9:45 but you were very close!
It couldn't possible be 9.45, the first bus runs every 20 minutes, so 00,20,40 past the hour.
Reply 9
Original post by FamilyFlags
I tried you time theory on my maths (the website) and it said it was not 9:40 but instead 9:45 but you were very close!
This thread is 8 years old.
If you've going to resurrrect it, to correct it, make sure you're right - the 20-min bus isn't even at the stop at 09:45.
(edited 7 years ago)
Reply 10
You find the LCM of 55 and 20 answer:220 (minutes)Then:you convert 220 minutes to hours and minutes which is: 3 hrs and 40 minutes and add it to 6amANSWER:9 hrs and 40 minutes 9:40
Reply 11
You lot were doing this question when I was 6 months old and now 13 years later I have this question btw answer is 9:40 I know u dont need this answer 13 years later but for anyone else
Related discussions
- Edexcel GCSE Mathematics Paper 1 Foundation (1MA1 1F) - 16th May 2024 [Exam Chat]
- Edexcel GCSE Foundation tier Maths Paper 3 3F (1MA1) - 14th June 2023 [Exam Chat]
- Muslim/general advice in maths💗
- Need help on maths foundation question Gcse
- help pls-urgent maths question!
- SOS medical microbiology research
- Studying abroad after access course?
- A-Level Choices
- KCL v Exeter - Pros v Cons PLEASE
- How to maintain focus, for real
- what do I take for A Level?
- LAE or LSC?
- Is there any video-based A Level course?
- Masters Degree After Several Years out - Worth it?
- GCSE Mathematics Study Group 2024-25
- WJEC GCSE Mathematics Unit 1 Higher (3300U50-1) - 16th May 2024 [Exam Chat]
- Pls can someone mark my AQA English Language paper 1? Thank you in advance!
- Advice as a muslim
- southampton uni accom 24/25
- Physics Students: At what age did you loose your virginity?
Latest
Trending
