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Ina_Shippy
Sep 17, 2009, 08:04 PM
There are 14 students in a class. If one student tells another student a message. 5 Minutes later each student that knows the message tells a new student. How long will it take for the class to know the message?

mudweiser
Sep 17, 2009, 10:04 PM
About an hour.

Sarah

Rhiannnonn
Sep 17, 2009, 11:48 PM
20 minutes

Rhiannnonn
Sep 17, 2009, 11:51 PM
No! 15 minutes!

kaalvoetkind
Sep 18, 2009, 12:13 AM
Less than 20 but more than 15...
Only 8 kids are going to know at the end of 15 so 20 then

ROLCAM
Jan 7, 2010, 06:07 AM
It will take 20 minutes for the
14 to know the message.

J_9
Jan 7, 2010, 06:46 AM
If one child is told the message every 5 minutes, it will take 70 minutes.

14 children x 5 minutes each child = 70 minutes.

NeedKarma
Jan 7, 2010, 07:01 AM
J9, it's not sequential, it's exponential.

J_9
Jan 7, 2010, 07:02 AM
J9, it's not sequential, it's exponential.

Oh, sorry... just got off work... brain not functioning properly. :o

J_9
Jan 7, 2010, 07:06 AM
I should know better than to do mathematical questions after a 12 hour shift.

NeedKarma
Jan 7, 2010, 07:37 AM
Sleep! I remember when I did 4 on/4 off 12hour shifts, days then nights. Crazy on the system. :)

J_9
Jan 7, 2010, 07:44 AM
Sleep! I remember when I did 4 on/4 off 12hour shifts, days then nights. Crazy on the system. :)

I typically do 4 on and 2 off. :eek: But a person who works 9 - 5 can't come home and go to bed at 5... I need some time to wind down as well. Guess I'll just stay away from simple math questions. Now, if the doc prescribes 150mg of antibiotics and all you have on hand is 375mg/2ml... I can do that in my sleep. :p