SOLUTION: Three bells ring at the interval of 10,15 and 20 minutes respectively . If they all ring at 11 a.m at once,what time they ring together again ? Please show process also and answer

Question 750562: Three bells ring at the interval of 10,15 and 20 minutes respectively . If they all ring at 11 a.m at once,what time they ring together again ? Please show process also and answer also.

Found 3 solutions by FrankM, reviewermath, ankor@dixie-net.com:
Answer by FrankM(1040)   (Show Source): You can put this solution on YOUR website!
We need the lowest common multiple of 10,15,and 20
10 = 2*5
15 = 3*5
20 = 2*2*5
These are the prime factorization for these numbers.
2*2*3*5 = 60 This is the lowest common multiple.
Noon is the answer.
Answer by reviewermath(1029)   (Show Source): You can put this solution on YOUR website!
The LCM of 10, 15, and 20 is 60.
After 60 minutes, they ring together again.
Answer: 12 noon
Answer by ankor@dixie-net.com(22740)   (Show Source): You can put this solution on YOUR website!
Three bells ring at the interval of 10,15 and 20 minutes respectively .
If they all ring at 11 a.m at once,what time they ring together again ?
:
Find the least common multiple of 10, 15, 20,
Prime factor
10: 2*5
15: 3*5
20: 2*2*5
then
2*2*3*5 = 60 is LCM
:
60 min from 11 is 12

RELATED QUESTIONS
three schools bells ring at intervals of 6,12 and 15 minutes respectively. If they ring... (answered by Edwin McCravy)
5 bells ring at interval of 15, 162, 6, 48, 18 seconds respectively. If the bells ring... (answered by htmentor)
Four bells ring at intervals of 6,8,12 and 20 minuts. They ring simultaneously at 10... (answered by ikleyn)
What is the answer if four bells ring simultaneously and afterwards at intervals of 3, 4, (answered by ikleyn)
Please help me on this question I tried but I couldn't do it. Three bells ring at... (answered by josmiceli)
At school, there are three bells. The first bell rings every 20 minutes, the second rings (answered by stanbon)
3bells ring at interval of 5mins, 12mins and 15 mins resptvly. They ring simultaneously... (answered by josmiceli)
School starts at 8:00 AM. A bell rings every 60 minutes, and another bell rings every 48... (answered by ikleyn)
A bell rings ever 8 minutes and another every 10 minutes. They both ring together at... (answered by Alan3354)