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Wednesday: Miss Marydoll’s, Eggciting Eggcellent, Eggsasperating, Eggceptional, Egg Puzzle.

(35 Posts)
Marydoll Wed 15-Apr-20 09:17:55

Good morning all you eggceptional mathematicians, here is today's puzzle.
If you click on the image, it will be easier to see.

How can you boil an egg for exactly nine minutes with only a 4-minute hourglass and a 7-minute hourglass to measure the time?

Doodle Wed 15-Apr-20 20:37:00

Oh ?

Marydoll Wed 15-Apr-20 20:36:19

Too late, I ate it!

Doodle Wed 15-Apr-20 20:29:18

Oh miss I’ve never had a star before ? mind you I would have preferred the chocolate ?

Callistemon Wed 15-Apr-20 19:39:38

Ooh, I got a star for Initiative

I'm always full of initiative, which means I am usually off piste.

Callistemon Wed 15-Apr-20 19:38:22

Thank you MissMary

My head was beginning to hurt

Marydoll Wed 15-Apr-20 19:35:42

Thank goodness, Willa has arrived, better late than never!

Bathsheba and Wila, spot on. ? for you.
Doodle ? for your poem.
Callistemon ?for initiative.

For my other favourite pupils. Pantglas, Gillybob and Feelingmyage, ? for being such good sports.

Here was the solution, I was going to post, before the others beat me too it.

ANSWER: Drop the egg in the boiling water and flip both hourglasses over. When the 4-minute hourglass runs out, flip it over. When the 7-minute hourglass runs out, flip it over as well. Now there is one minute left in the 4-minute hourglass. When it runs out, 8 minutes will have elapsed and there will be 6 minutes left in the 7-minute hourglass. Flip over the 7-minute hourglass again. A minute later the 7-minute hourglass will run out and a total of 9 minutes will have elapsed.

PS:, I'm not sharing my chocolate stash, Doodle. wink

Doodle Wed 15-Apr-20 19:10:31

willa’s late but never fear
It always more fun when she is here
She lives in a land far away
So it takes her longer to get here and play?

Doodle Wed 15-Apr-20 19:08:35

pantglas and willa thanks for joining in. Butter wouldn’t melt pantglas oh yeah ?

willa45 Wed 15-Apr-20 18:14:41

Willa's late,
They locked the gate
She didn't run
and missed the fun,
but here's her homework...no harm done

Nine minute eggs

Start both timers at the same time (Call the 7 min, 'Big' and the 4 min, 'Little').

After 4 min, Big has 3 min of sand left and Little is at zero. so we must flip Little a second time.

After 3 min, Big is now at zero and there's still 1 minute left in Little. (7 minutes have elapsed) Flip Big.

While (eight) minute from Little elapses, Big is dropping its own minute of sand on the bottom. and has 6 minutes of sand remaining on top ( at this point, 8 minutes have elapsed).

Flip Big so that 1 min of sand is now on top and the other six on the bottom. Now you can measure your extra minute and that's how you get to minute 9.

Callistemon Wed 15-Apr-20 17:46:37

Doodle grin

Callistemon Wed 15-Apr-20 17:44:14

It was one of those puzzles which just kept eluding me, there at the edge of my brain but kept disappearing grin

Pantglas2 Wed 15-Apr-20 16:54:20

Well it’s obvious now who’s gonna be Teachers Pet
A more blatant attempt I’ve not seen yet
Might ave guessed it’d be Naughty Doodle
She’s quite good at using her noodle
To get the rest of us up Schitts Creek
Unlike me - who’s mild and meek
And in who’s mouth butter wouldn’t melt
Yikes! Miss has caught me, I’m getting the belt!

Bathsheba Wed 15-Apr-20 16:09:04

OK, so here's my explanation for what it's worth:

Set both timers
When the 4 minute one has finished, turn it over and restart it;
When the 7 minute one has finished, turn it over (there is now 1 minute left in the 4 minute one);
When the 4 minute one is empty again, turn the 7 minute one over quickly - it has only filtered one minute's worth of sand through to the bottom, so when this has gone back through, you'll have had 2 x 4 minutes worth and that 1 minute from the 7 minute one, making 9 minutes in total.

Phew, that looks ever so confusing Miss, sorry. I hope it makes sense blush

Marydoll Wed 15-Apr-20 14:55:17

Oh, I absolutely love it!! ?

Doodle Wed 15-Apr-20 14:52:23

Miss Marydoll - a poem

To keep the Netters on their toes
And stop them thinking of their woes ?
Miss Marydoll’s gone back to teaching
Keeping our brains from atrophying ?

Miss Marydoll’s class is full of fun
And well behaved apart from some ?
That doodles known to be a corker
Constantly being out of order ?

Gillybob’s been naughty too
Had to join the detention queue ?
And squiffy’s dog, what can you say ?
I expect she’ll bring him back one day!

Pantglas posts a teasing wheeze
Then hides her head between her knees ?
callistemon cannot boil an egg
She calls on Alexa to time it instead ?

Bathsheba‘s got a clever reply
But not the right one my o my.?
feelingmyage has just come in
Oh my goodness ? where’ve you bin.

Many others come to play
So where have they all gone today.?
Come back to class before I tell,
Your missing, when we ring the bell ?

S

Doodle Wed 15-Apr-20 14:16:59

bathsheba that’s a brilliant idea. (Alexa) wish I’d thought of it.
feelingmyage you’re even later than me. Perhaps I can get off the norty seat now.

I tried Miss I really did but I got so caught up with 7 minus 4 and 3 with one left I kept getting it wrong. Sorry ?

Doodle Wed 15-Apr-20 14:04:22

pantglas you fibber ? I wasn’t even in class when you did that. Oops.. sorry I was late again Miss

Doodle Wed 15-Apr-20 13:57:40

Now to the quiz.

Doodle Wed 15-Apr-20 13:57:26

Miss Doll I think you’ve been eating too much of that chocolate you found in your linen cupboard. Your title thread leads me to believe you are like my DGC when they have excess of chocolate...hyperactive grin

Feelingmyage55 Wed 15-Apr-20 13:37:54

Just arrived and it is finished. Please may I clean the blackboard miss?
Is there another little one? I’ve just started to “think” this week?

Callistemon Wed 15-Apr-20 11:48:43

Alexa - help!!

Even coffee and mini eggs aren't helping today

Bathsheba Wed 15-Apr-20 11:34:00

Miss, Miss it's not fair. Pantglas has written how to do it and that's how I did it and I was going to wait till later to explain it and now it looks as if I just copied her sad

Pantglas2 Wed 15-Apr-20 11:20:42

I’m still here on the naughty stool Miss.....Woz I rite?

Marydoll Wed 15-Apr-20 11:17:50

GNHQ have stolen my thunder with their daily challenge. sad.
I'm all alone in my classroom. ?

Pantglas2 Wed 15-Apr-20 10:10:42

Okay, thinking out loud...

Turn both egg timers over and when the 4min finishes turn it over again. When 7 min finishes put eggs on to boilgiving 1min until 4min finishes. You then do two more turns on the 4min timer, giving 9 minutes in total.