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. 3)
3.
Six bells commence tolling together and toll at intervals of 2, 4, 6, 8 10 and 12 seconds respectively. In 30 minutes, how many times do they toll together ?
Answer: Option
Explanation:
L.C.M. of 2, 4, 6, 8, 10, 12 is 120.
So, the bells will toll together after every 120 seconds(2 minutes).
| In 30 minutes, they will toll together | 30 | + 1 = 16 times. |
| 2 |
Discussion:
170 comments Page 3 of 17.
Vairam said:
1 decade ago
Why 1 is added?
Naveen said:
1 decade ago
Really good explnation.
Lakshmisha said:
1 decade ago
@Sravanreddypailla, excellent dude...!!!
Sangeeta said:
1 decade ago
I didn't understand why did we add 1?
Please explain.
Please explain.
Malatha said:
1 decade ago
I also didn't understand why did we add '1'? please tell me.
BALARAJU HARI said:
1 decade ago
Its simple, according to the shortcut formula everyone understood why the tolling together takes place at every 120sec(2min) period from the l.c.m concept.
But why 1 is added means, it is clearly mentioned in the question that the 6 bells starts tolling together at the starting stage(first tolling is done by together) and tolls at the intervals 2, 4, 6 ,8, 10, 12. so, before tolling together at 120sec(2min), they already tolls together at the 1st(zeroeth sec i.e starting) itself. so that 1 is added.
But why 1 is added means, it is clearly mentioned in the question that the 6 bells starts tolling together at the starting stage(first tolling is done by together) and tolls at the intervals 2, 4, 6 ,8, 10, 12. so, before tolling together at 120sec(2min), they already tolls together at the 1st(zeroeth sec i.e starting) itself. so that 1 is added.
Aashish said:
1 decade ago
Thanks sundar. Amazing explanation!
Vasu said:
1 decade ago
Thanks to both Sravan and Sundar for your explanation.
Fozia sheikh said:
1 decade ago
Four bells toll after intervals of 8, 9, 12and 15minutes, respectively. If they toll together at 3pm. When will they toll together next?
Ramesh said:
1 decade ago
Awesome sravan!!
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