First, for those of you going to the Cheltenham Literary Festival, I am doing a joint event about the paranormal with writer A L Kennedy on Saturday. Details here.
OK, here is the puzzle.
John and Erica live together and between the two of them have three chores to perform. The chores are (i) vacuuming the floors, (ii) mowing the lawn and (iii) feeding the baby. Each of the chores takes thirty minutes, and they only have 1 vacuum cleaner, 1 mower and 1 bottle of milk. What is the shortest amount of time in which John and Erica can complete the chores?
As ever, please do NOT post your answers, but do say if you think you have solved the puzzle and how long it took. Solution on Monday.
I have produced an ebook containing 101 of the previous Friday Puzzles! It is called PUZZLED and is available for the Kindle (UK here and USA here) and on the iBookstore (UK here in the USA here). You can try 101 of the puzzles for free here.
Heheh the moment I started to think this was way too easy it hit me
one minute – had to scribe a diagram
I made a diagram too! I got an answer in about two minutes, but I’m only 99% certain it’s correct.
Got it
If it was a ride on Mower could I mow while feeding the baby?
I really don’t like chores!
What chores? I’ll have a pint thanks!
Got two answers, depending on the skills of the baby.
Can babies multi-task?
I also have two answers, depending on baby.
If it was a single mother, the answer would be simple: “5 minutes, while she’s baking the cake, doing the dishes and organising the child minder”.
They don’t need to cut the grass as they have a couple of cows in the garden who chew it right down to a lovely length!
And give milk! so the answer is 30 minutes!
A minute thinking it was too easy, then a second realisation that my answer was too slow. 1mim and 1 second total for the answer.
who to say they won’t call in a nanny, a house keeper and a gardener while the wife watches Oprah reruns and the husband play Xbox games. but i do think i have the answer
oh, then they would have to own two tvs…
suburbs folks r rich! tv in tv room, tv in kitchen, tv in bed room, tv in workout room.
It critically depends three factors:
1 what percentage of each chore can each perform unattended by the other?
2. are the chores interruptable and resumeable?
3. do the vacuum and mower have separate power leads?
Can you stop vacuuming and resume later?
You can answer that question right?
> You can answer that question right?
It seems to me that is the core question. If each chore has to be done in one go, the total time needed would be different.
So if, say, one of the three tasks was skydiving rather than lawn mowing, we’d get a different answer
It seems too easy, am I missing something?
As is often the case with these puzzles this is either incredibly obvious, or I’ve misunderstood it. Knowing me, probably the latter.
10 seconds for a couple of answers, depending on whether or not you have a one-handed vacuum and a sling that can hold a feeding baby….
Hey, this is similar to one I just posted on my blog…
http://adenozine.tumblr.com/post/11289400421/maths-puzzle
A project manager’s dream question
There’s a baby involved and they’re trying to do the chores in the shortest time possible. Therefore it will take all day.
lol
I live in a country manor get the sevants to it. What!!!
Drew a diagram and then it was obvious.
i think it is easy,
The second solution would require a record player of the manufacturer “dual”… or a baby carryage,…
They must have a big house if it takes half an hour to vacuum it!
Well i got an obvious answer in about 10 secs so as usual I’m doubting my answer as it seemed to easy.
Surely it depends on if the milk is bottle or tit
I’ve got an answer that’s probably the one that’s intended (as indicated by the ‘bottle of milk’ statement), but if she breastfed and used a sling, it’d be faster (as I see someone has also stated above).
Divide and conquer!
under a minute
got it before i finished reading the question – so does that count as negative time?
This is similar to “how long to cook three burgers when only two can be grilled at a time, and each side of each burger needs to cook for 1 minute”.
With Richard’s puzzles, if the answer is obvious, there is usually a catch. With this one, I don’t think there is
Now, this is outrageously impossible!
Horrible puzzle!
I have two answers. One depends on who the baby is.
Yep, same as my answer.
I have 3 different answers.
One with no premises added.
One with obvious premises added.
One with super crazy premises added.
36s
Three hours. John’s a guy and refuses to help with feeding or vacuuming. Erica gets mad and storms around the house yelling at John. John goes down to the pub for a pint. Erica is left to do everything by herself. The baby’s nap is interrupted by the vacuuming, and then the kid won’t take the bottle. John gets back to the house to find Erica carrying the baby while trying to vacuum. John figures it’s better to stay outside so decides to mow the lawn. By the time he’s finished, the vacuuming has calmed the baby, Erica is talking to him again, and the baby will finally take the bottle. Happened to me just last week (though my name’s not John).
do they own a roomba?
Why isn’t she breastfeeding? Unless maybe she expressed…?
I don’t suppose either of them can multitask…
I think I’ve got it. Did not time myself, but under a minute to arrive at my answer. (I like Kirsty’s suggestion, though. Definitely rings true!)
Hmm, well… I got an obvious answer in about 20 seconds, but I’m now thinking its a little TOO obvious based on so many clever comments. Hmm.
The Surgeon was his mother.
I got it in like 5 seconds but realised it couldn’t work, then annoyingly I got the same answer but in a different way. 40 sec
2 answers, one of which is realistic but vague.
I got it instantly… as soon as I read it. Which makes me suspect I’m missing something.
Well I think I have solved it but really need to know the answer from you before I pat my back ! ! !
Check the brainteasers here –
http://www.iqtestexperts.com/brainteasers/
Really tired of math word problems like my school textbks. that made me hate math forever. P.S. Did very well with farmer brown and which car or train wins and math in general. Just bored me ever since. Even my math wizard husband has tired of these puzzles.
About 20 sec. Answers from RyderDA and Kirsty were pretty good. And seeing these chores are repeating, the answer could be “never”.
Can the baby hold the bottle by himself? We do not know how old he is. The baby could be breastfed even if they have a bottle at home. Do they have a babycarrier to feed the baby while vaccum cleaning? And are they high tech people with good salaries? Does the vaccum cleaner cleans on its own? Same question for the mower.
I “solved it” right away. It seems too easy to be correct. I am assuming either the baby can hold the bottle itself or one of the parents wears a Baby Bjorn.
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