[OT] Simple arithmetic

[Dave Plowman (News)]

If an error of nearly 1mm is ok for your purposes, 10/10. ;-)

[whisky-dave]

I got 9 on my iphone and 9 using google.

[Judith]

That's the point : it should be 2.071067818 ;-)

[Judith]

A simple non-mathematical solution could be to say that the circle and square are both symmetrical about both diagonals - so it has to be the centre of the circle.

[The Natural Philosopher]

Its implicit in the proposition that he drew a square as small as possible ROUND the circle and exactly in the same place AS the circle.

By symmetry, both must have their centres co-incident.

[Max Demian]

Well doing it in my head gives 1. Windows Calculator (Scientific mode) gives 9 (so does my TI scientific calculator), but you have to insert a x between the 2 and the (, as it doesn't understand that a value next to a ( means that you have to multiply the value with the result of the contents of the brackets, and this takes priority over the division.

[Robin]

1. There's a missing operator
2. BODMAS

[Max Demian]

In (written) algebra, a value before a left bracket means multiply the result of the contents of the brackets (first).

[Judith]

Really? How about default to multiplication - is that no longer the rule?

so 6÷2 *3 = 1

(Unless something incorrectly gives you 9 of course)

[Graeme]

In message , "Dave Plowman (News)" writes

Well, a tad over two feet was close enough :-)

[Robin]

Do iPhones know that? I don't have one.

PS I assumed you meant key into the phone *exactly* what you posted.

[whisky-dave]

Like this you mean

[Mark]

both 1 and 9 are correct depending.....

-

[Huge]

... on whether you're a f****it or not.

[The Natural Philosopher]

...on operator precedence.

Just like punctuation, if you don't have rules that everybody sticks to, language is ambiguous

[The Natural Philosopher]

No, it depends on what 6/2*3 is held to be.

And whether you consider there is an implicit bracketing of 2(1+2)

[AnthonyL]

You mean in like "Let's eat grandma?"

[The Natural Philosopher]

Exactly.

Or Eats, Shoots, and Leaves.

[NY]

I was taught BODMAS (brackets, orders (powers), division, multiplication, addition, subtraction) as the order in which to apply operators.

So:

- evaluate 1+2 first because it's in brackets.

- there are no orders/powers

- evaluate 6 / 2 = 3

- evaluate 6 (ie 6/2) * 3 (ie 1+2)

- there is no addition or subtraction (other that 1+2 which was evaluated early because it's in brackets).

Therefore the answer is 9.

On the other hand, should the 2(1+2) be evaluated before the division because a gut feeling says that an implied multiplication should have a higher-than-normal precedence - and it *is* only gut feeling: I couldn't explain why!

I'd have written the expression with a few more brackets to make it abundantly clear what I meant: so either

6 / (2(1+2)

or

(6/2)(1+2) aka (6/2)*(1+2)

[The Natural Philosopher]

Exactly.

Relying on operator precedence when it's very shaded is a bad idea.

AS is relying on implicit type conversion in a boolean operation, as I also know to my cost.

Javascript type casting is defined for assignment, but not for comparison.