Math Is Fun Forum

  Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

You are not logged in.

#1 2005-07-01 04:41:55

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Crooked Clocks

Alfred, Benjamin, Cuthbert, Donald, Ernie and Fred each have a special clock, and they all have a special property.

They all have a butler who hears the church bell chime the hour and so rushes around to set each clock to the correct time, since they mostly don't keep it themselves...

Alfred's clock shows the correct time.
Benjamin's clock has lost 2 hours and 5 minutes since being set.
Cuthbert's clock runs at half-speed.
Donald's clock is broken.
Ernie's clock gains 10 minutes every hours.
Fred's clock works backwards.

At the moment, the clocks read 10:30, 5:30, 12:45, 7:05, 3:25 and 8:00, in no particular order.
What is the time now?


Why did the vector cross the road?
It wanted to be normal.

Offline

#2 2005-07-03 22:52:34

MathsIsFun
Administrator
Registered: 2005-01-21
Posts: 7,711

Re: Crooked Clocks

I kind of understand BUT if the butler hears the church bell chime the hour, how can one clock (Benjamins) be more than one hour wrong. Do we assume the church bell does not chime at night?


"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

Offline

#3 2005-07-04 04:04:19

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: Crooked Clocks

Sorry, I forgot to mention that the butler only did that once. This means that the amount of time passed since he did that could be, and is, more than an hour. Also, the clocks are all analogue, so they display 12-hour time.


Why did the vector cross the road?
It wanted to be normal.

Offline

#4 2005-07-04 20:26:16

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,829

Re: Crooked Clocks

Clue No.1 :- First, figure out what time the clocks were set


It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Offline

#5 2007-03-16 17:46:49

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

Re: Crooked Clocks

5:30.

You only need the first two clues. Then just look at which two times differ by 2 hours 5 minutes.

Offline

#6 2007-03-17 00:01:54

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: Crooked Clocks

Heh, nice solution. I completely missed that.


Why did the vector cross the road?
It wanted to be normal.

Offline

#7 2007-03-17 10:15:08

justlookingforthemoment
Moderator
Registered: 2005-05-26
Posts: 2,161

Re: Crooked Clocks

Going green now, mathsy? big_smile

Offline

#8 2007-03-17 10:28:06

lightning
Real Member
Registered: 2007-02-26
Posts: 2,060

Re: Crooked Clocks

going blue justlookingforthemoment? big_smile lol
and our colours match our avatar strange but cool

Last edited by lightning (2007-03-17 10:29:16)


Zappzter - New IM app! Unsure of which room to join? "ZNU" is made to help new users. c:

Offline

#9 2007-03-17 10:51:32

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: Crooked Clocks

justlookingforthemoment wrote:

Going green now, mathsy? big_smile

It's to celebrate St. Patrick's day. So going by Greenwich Mean Time, I've got about an hour of greenity left. rolleyes tongue


Why did the vector cross the road?
It wanted to be normal.

Offline

#10 2007-03-17 10:57:08

justlookingforthemoment
Moderator
Registered: 2005-05-26
Posts: 2,161

Re: Crooked Clocks

Ohh right! That makes a lot of sense! Happy St Pat's Day.

Offline

#11 2007-03-17 10:57:14

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

Re: Crooked Clocks

Ooh …

And Ireland sooo almost won the Six Nations today. What a shame. sad

Offline

#12 2007-03-17 21:57:15

lightning
Real Member
Registered: 2007-02-26
Posts: 2,060

Re: Crooked Clocks

i think i will go wait let me see if theres gold.....
happy st patrick dayhappy patricks day


Zappzter - New IM app! Unsure of which room to join? "ZNU" is made to help new users. c:

Offline

Board footer

Powered by FluxBB