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Bunuel
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Abhishek009

Bunuel
You and your partners set your alarms for 6:00 am. If your alarm repeats every 12 minutes and your partner's repeat every 18 minutes, at which of the following times could both of your alarms go off ?

A. 6:30 am
B. 6:48 am
C. 7:00 am
D. 7:48 am
E. 8:12 am
\(LCM (12, 18) = 36\)

Following are the time for the clock to repeat, 6:36 AM (Not in option) , 7:12 AM (Not in option) then 7:36 AM Option (D), Answer must be (D)
 
­Can you elaborate please? option d is 7.48 am , not 7.36 am. Following your method, 8.12 should be the answer which is E, as 8.12 just comes after 7.36, but OA is D

 
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kopp74

Abhishek009

Bunuel
You and your partners set your alarms for 6:00 am. If your alarm repeats every 12 minutes and your partner's repeat every 18 minutes, at which of the following times could both of your alarms go off ?

A. 6:30 am
B. 6:48 am
C. 7:00 am
D. 7:48 am
E. 8:12 am
\(LCM (12, 18) = 36\)

Following are the time for the clock to repeat, 6:36 AM (Not in option) , 7:12 AM (Not in option) then 7:36 AM Option (D), Answer must be (D)

 
­Can you elaborate please? option d is 7.48 am , not 7.36 am. Following your method, 8.12 should be the answer which is E, as 8.12 just comes after 7.36, but OA is D


 
­I am assuming this was just an error while they typed the comment.

Considering the LCM, the alarms ring at the same time every 36 minutes. Starting at 6:00 am gives us: 6:36 am, 7:12 am, 7:48 am, 8:24 am. Only the third is an option, hence the answer is D.
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