help me as my brain has gone to mush...
That's what I said!
8 + 4 - 9 x 3 = 24
or am I too late!
I have a circular field (well paddock pen) and I have horse ..... I am sorely tempted to go outside and try rope thing at lunchtime
Ah shoot! I read the question wrong.
I got = [(r^2)/2]^(-1/2)
but that's if you tie the cow to the centre of the field. I admit I couldn't work it out if I'd read the question properly. I'm lame with Sin, Cos and Tan.
Garr - yes I know the first one was a bit easy! My excuse is that my boys have very kindly given me their cold and my head is full of goo
(plus, these being the not so bright members of the class, I was looking for really easy solutions, so having to do several steps to get to 3x8 is a bit difficult for them!)
8 + 4 - 9 x 3 = 24 should of course have read 8 + 4 - 9 x 8 = 24
Thank you Barkles. I will now write out 100 times 'I must not forum without my glasses on'
Do I have to see you after school for punishment too?
Thanks Stump. I knew I got it wrong only when I saw the answer.
Fraggle, don't worry, I wasn't saying you should've got it. There are plenty of times I should've got things but my brain just let's me down at the last moment. I'll never forget getting 99% in a calculus test because I managed to add 7 and 6 together to get 15!! If you start looking in the wrong direction with something like that question, you might spend days trying to get the answer.
Do we know the problem below (which I'm not going to name because it'll be too easy for people to pull out the solution)? It's always a cracker to share with people.
The "XXXXX XXXX" problem
Imagine you're in a game. There are 3 doors in front of you which you cannot see behind. There is only you and the quiz host in this game.
Behind 2 doors are coconuts, and behind 1 door is a luxury yacht (they're big doors, ok?). Now, we'll assume you always want the luxury yacht, just in case there's anyone out there with a bizarre coconut fetish!
You are asked to pick a door.
The quiz host now removes one of the other doors (but he will never take away the luxury yacht because that'd be a pretty naff game).
You are then told you can either stick with the door you have chosen, or you can change to the other door. Remember, you still can't see what's behind either one.
What should you do?Should you stick, change, or does it make naff all difference either way?What are the probabilities each way?
NB - this is a question often used to show how straight forward logic can get the wrong answer and unpleasant, but well formulated maths will prevail, BUT if you are careful with your logic, you'll get it right.
I know that one Garr - I was about to post the same problem myself. It's a great example.
TP - that's still not right unless you write (8 + 4 - 9) x 8 = 24
8 + 4 - 9 x 8 = is 8 + 4 - 72 = -60
left to right associativity is only true for operators of the same precedence.
here's another I like because it shows that our gut feeling on conincidence is often wrong
All twenty-five of my students want to invite me to their birthday party. What is the probability that I get at least two invites for the same day?
It's a lot higher than you would guess.
Been a long time since I was at school but don't think you do need the brackets. If you follow the sum along the line and key it into a calculator as it stands the number at the end is 24.
left to right associativity is only true for operators of the same precedence - Sorry, I have no idea what this means - not only been a long time since school but I was never very good at arithmetic .... that's why I'm an accountant
Visit the official Runner's World page
Follow Runner's World on Twitter
Other Natmag-Rodale Sites
Run For Charity
About Runner's World
Runner's World is a publication of Hearst Magazines UK which is the trading name of The National Magazine Company Ltd, 72 Broadwick Street, London, W1F 9EP. Registered in England 112955. All rights reserved.
Website powered by: Immediate Media Company Ltd. | © Runner's World 2002-2013 |