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Dar
11-05-07, 04:33 PM
All you school kids and sientifical types will/should get this in a snap.

You have accidentally left the plug out of the bath, and are attempting to fill it with both taps on full.
The hot tap takes 6 minutes to fill and the cold tap takes 4 minutes to fill and the water empties thru the plughole in 12 minutes. In how many minutees will it take to fill the bath with the plug out?

Adam
11-05-07, 04:36 PM
5?

coombsey
11-05-07, 04:37 PM
id say 2

Mike
11-05-07, 04:40 PM
What did the bath tub say to the toilet?




you may get more a-s-s than me but i don't take s-h-i-t from none!!

Adam Moran
11-05-07, 04:45 PM
Trick question

There will never be enough "flow" from the taps to fill the bath with the plug out

nov4801
11-05-07, 04:45 PM
none as the plug is already out

Dar
11-05-07, 04:52 PM
Nope both 5 & 2 are wrong answers.
The point of the riddle is that the flow in is greater than the flow out. So the bath WILL fill up. Come on get that brain cell warmed uplol

wisewood
11-05-07, 04:52 PM
3 minutes 20 seconds.

Dar
11-05-07, 04:54 PM
Not 3mins 20secs either.

Dar
11-05-07, 04:56 PM
It would also be intresting to see your workings out.

wisewood
11-05-07, 04:56 PM
treating a full bath as 100% - and work from there... as it is the constant variable that you know you can work from.

1. 100/4 minutes = 25% full per minute
2. 100/6 minutes = 16.6% full per minute

Both taps are running so add them together.
Total flow rate = 41.6% full per minute.

However, the plug is out.

3. 100/12 = 8.33% per minute
4. 41.6 - 8.33 = 33.27%

So the bath fills by roughly one third every minute. So three minutes and 20 seconds and it should be full :D

Adam Moran
11-05-07, 04:56 PM
14 mins

Dar
11-05-07, 04:58 PM
Wisewood soooooooooo close. Im not going to tell you where you went wrong though. But you will go Doh!!

Riggy
11-05-07, 04:58 PM
2 1/2 min ?

wisewood
11-05-07, 05:00 PM
ok - not working the decimals - 3 minutes lol

Dar
11-05-07, 05:01 PM
Riggy - No and where are your workings out:confused:
Don't guess.

Dar
11-05-07, 05:02 PM
ok - not working the decimals - 3 minutes lol
lol Welldone. Spot on:thumb:

Now who can tell me how long it will take to fill the bath with the plug in? (Not Mr Wisewood, hes too Wise)

Riggy
11-05-07, 05:04 PM
lol well you said the cold tap takes 4 min to fill with the plug already out , so i divided 6 by 4 which gives you 1.5 min

took that away from the 4 , which gives you 2.5 min

Dar
11-05-07, 05:17 PM
Another way to work out the plug out scenario.

Taps flow = 1/4+1/6 = 10/24 = 5/12
Plug hole flow = 1/12

Over all flow = 5/12 - 1/12 = 4/12 invert it and you get 3mins

Adam
11-05-07, 05:23 PM
I never saw the "With plug out bit" lmao lol

Dar
11-05-07, 05:27 PM
lol pillock!