souphound wrote:We are working with base-10 numbers, yes?
Yes.
souphound wrote:We are working with base-10 numbers, yes?
Footy wrote:Last week, I discovered that the cordless drill I bought about 5 years ago is, in fact, a cordless screwdiver.
souphound wrote:I've got it. You have 230 dogs. 220 of them escape into the wild. Of the 10 left, half are halfwits. You're left with 5 good dogs and 5 headaches?
Hightea wrote:No its not its 120
BIDMAS
no brackets - skip
no division - skip
multiplication - 220 * .5 = 110
none addition
subtraction 230 -110 = 120
explain how you are getting 5?
Positive Passion wrote:I expect the - is not a minus sign, but instead denotes a range or something - there is something like this in set theory - so range is 230 to 220 - which halved is 5.
Positive Passion wrote:It had you confounded for 5 minutes?
Charlie O. wrote:Factorials.
Rorschach wrote:Positive Passion wrote:It had you confounded for 5 minutes?
Yes! And i was annoyed with myself for taking that long. It's actually very simple if you know the mathematical symbols, but I'm worried now that people don't know the relevant one.
It's come up in maths problems on here before and, as i said, Carlsson will spot it straight away, but if you don't know it, then it's impossible.
So it's a bit mean to post it in that case.
Do you want me to explain it?
Rorschach wrote:OK.
the symbol '!' in maths is known as 'factorial'. Any number followed by '!' is then multiplied by all integers between itself and one.
So 5! = 5 X 4 X 3 X 2 X 1, which equals 120.
Rorschach wrote:Did you spot it immediately, or did it puzzle you for a bit?
Positive Passion wrote:A curmudgeon writes:
It would have been completely obvious if as well as getting the maths right, your English was up to scratch. If the ! Is a mathematical symbol, then the sentence should end with a full stop. I would have got it instantly then.
The Prof wrote:The actual calculation is 2 lines down from the exclamation mark - so the exclamation mark doesn't count
The Prof wrote:The actual calculation is 2 lines down from the exclamation mark - so the exclamation mark doesn't count