Go to navigation
It is currently Sat Dec 10, 2016 6:32 pm

All times are UTC




Post new topic Reply to topic  [ 3 posts ] 
Author Message
PostPosted: Sun Oct 21, 2007 12:02 pm 
A computer checks e-mails and news updates on a regular basis.In a 24 hour period,the computer checks e-mails every five minutes and news updates every seven minutes.Neither work when both checks are being done at the same time and this causes an error message on the screen.There is one error message after an hour and three error messages after two hours.How many error message are there after 24 hours?
Answer 41


Top
  
 
 Post subject:
PostPosted: Sun Oct 21, 2007 12:13 pm 
Offline

Joined: Wed Aug 01, 2007 11:19 am
Posts: 888
The error message will appear every 35 minutes.

35 is the lowest common multiple of 5 and 7 - i.e. the first time that something happening every 5 minutes and something happening every 7 minutes will happen at the same time will be after 35 minutes.

Checks mail - 5, 10, 15, 20, 25, 30, 35
Checks news - 7, 14, 21, 28, 35

Then every 35 minutes after that.

The once after one hour, three times after two bit is irrelevant, though true (first three errors will be at 35 mins, 70 mins, 105 mins).

24 hours = 1440 minutes
1440/35 = 41 (and 5 remainder)

So 41 error messages.


Top
 Profile  
 
 Post subject:
PostPosted: Thu Jan 10, 2008 8:45 pm 
Offline

Joined: Tue Jan 01, 2008 1:05 pm
Posts: 515
aliportico wrote:
The error message will appear every 35 minutes.

35 is the lowest common multiple of 5 and 7 - i.e. the first time that something happening every 5 minutes and something happening every 7 minutes will happen at the same time will be after 35 minutes.

Checks mail - 5, 10, 15, 20, 25, 30, 35
Checks news - 7, 14, 21, 28, 35

Then every 35 minutes after that.

The once after one hour, three times after two bit is irrelevant, though true (first three errors will be at 35 mins, 70 mins, 105 mins).



24 hours = 1440 minutes
1440/35 = 41 (and 5 remainder)

So 41 error messages.



The once after one hour etc. information is not entirely irrelevant. It fixes the start point. Without this info there is no other information that confirms when the first error message occurred. This affects the remaining time into which the divide the common multiple. However, in this example, as far as I can recall,the multiple choice answer options do make the info. irrelevant.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 3 posts ] 

All times are UTC


Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
CALL 020 8204 5060
   
Privacy Policy | Refund Policy | Disclaimer | Copyright © 2004 – 2016