Aptitude - Problems on H.C.F and L.C.M - Discussion
Discussion Forum : Problems on H.C.F and L.C.M - General Questions (Q.No. 15)
15.
A, B and C start at the same time in the same direction to run around a circular stadium. A completes a round in 252 seconds, B in 308 seconds and c in 198 seconds, all starting at the same point. After what time will they again at the starting point ?
Answer: Option
Explanation:
L.C.M. of 252, 308 and 198 = 2772.
So, A, B and C will again meet at the starting point in 2772 sec. i.e., 46 min. 12 sec.
Discussion:
66 comments Page 2 of 7.
Arvind Kumar said:
8 years ago
Whenever we need to find a number which will get divisible by certain numbers completely we take lcm. On the other case, if we need to find the number which will divide certain numbers completely we take HCf.
Here in case, we need to find the number which gets completely divide by 252, 308 & 198 that is why we are calculating LCM.
Here in case, we need to find the number which gets completely divide by 252, 308 & 198 that is why we are calculating LCM.
(1)
Shweta said:
9 years ago
@Liana.
To convert into minute = 2772/60 = 46 min and remainder is 12.
That's why 46 min 12 sec.
To convert into minute = 2772/60 = 46 min and remainder is 12.
That's why 46 min 12 sec.
(1)
Gargi said:
9 years ago
If LCM is 2772 then why we are dividing 2760 by 40?
(1)
Isha said:
5 years ago
Thanks all for explaining the answer.
(1)
Kiran soni said:
1 decade ago
How can I quickly find 2772 LCM ?
Please reply.
Please reply.
(1)
Sujay said:
1 decade ago
When to take lcm and when to take HCF is confusion ? please help.
(1)
Luci said:
4 years ago
@Giridhar.
Can you explain in more detail? Please.
Can you explain in more detail? Please.
(1)
Vijay said:
8 years ago
2772/60 = 46 min and remaining 12 sec.
or
2772/60=>693/15=>231/5 = 46 min 1/5.
1/5 =1 * 60/5 = 12 sec.
46 min 12 sec.
or
2772/60=>693/15=>231/5 = 46 min 1/5.
1/5 =1 * 60/5 = 12 sec.
46 min 12 sec.
Prahlad said:
8 years ago
2772 /60 =924/20 = 46minutes 4 seconds.
But 2772 /60 = 46minutes 12 seconds.
But 2772 /60 = 46minutes 12 seconds.
Jothi said:
8 years ago
Why we take LCM for this problem? How to understand. Anyone please tell me.
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