Anyone up for solving this puzzle?

[summeriscomingsoon]

A gold star for a correct answer



@DadDadDad

To the posters who say BIDMAS wasn't a "thing" when they were at school... out of interest how old are you?

I think I've discussed this on MN before, but it seems it became popular in the 80s/90s. The principles it encapsulates have remained unchanged in normal algebraic convention for what must be centuries, but the use of BIDMAS in the classroom as a teaching tool is more recent. (I only remember coming across it in the 90s when I became a secondary school maths teacher).

I'm 73 and it was most certainly a 'thing' then, without it the whole of mathematics since the start of recorded sums falls down as it would be open to discussion.

But if you know the rules of operator precedence that spreadsheets use, there is no ambiguity and you can omit superfluous brackets.

Not just spreadsheets, every computer language I've come across uses the same order of precedence for maths operations.

And we were taught it in school anyway. Anyone who doesn't know to do divisions and multiplications first if there are no brackets to say otherwise either wasn't paying attention or has forgotten.

[quote diddl]I also remember working out sums/products simply from left to right.

www.teachwire.net/news/why-its-time-for-maths-teachers-to-bin-bodmas[/quote]
Then you were taught bady. Just because lazy people publish rubbish doesn't make it right!

It's impossible to deduce the correct answer.

Simply because a picture of a pair of bananas=2, that does not prove that one banana=1. Otherwise by that logic, 3 must be a picture of 3 bananas, and 10 would be 10 bananas, not a cookie with 10 chips.

This is rubbish!

24

I'm 60, I don't remember ever being taught the acronym BODMAS - we were just taught the standard precedence rules and expected to remember and apply them.

Simply because a picture of a pair of bananas=2, that does not prove that one banana=1. Otherwise by that logic, 3 must be a picture of 3 bananas, and 10 would be 10 bananas, not a cookie with 10 chips.

I guess you struggle with Roman numerals?

11

(7x1)+1+3

25

@Whythesadface

Things were changed because calculators and computers were used. Just use the brackets for gods sake, that's what they are for. ( DO THIS FIRST)

That's not true. I was just having a browse through Isaac Newton's Philosophiæ Naturalis Principia Mathematica (I know, I know, but Google books has an English translation online), and he was using the convention back then: if he wrote A x B + C x D it was understood to mean do the multiplication first. And that was 17th Century - he didn't have a calculator...

10!

There are no brackets so if you want to do the calculation from left to right then you would need brackets. Brackets around the multiplication at the end would be redundant.

@oneglassandpuzzled

11

(7x1)+1+3

Where do you get the 3 from? Look again.

11

Sorry, meant 10

10

70

No, meant 11

@DadDadDad

Thanks for that *@PhillipPhillop*. I seem to recall someone in a previous discussion remembering it from the 70s, so fascinating to hear how its origins go back before that.

I'm 48 and I've never heard of Bodmas. We were only taught maths with brackets when I was at school. In fact, we were taught that it was impossible to calculate equations without brackets and that equations didn't make sense without them. Clearly my school was shit!

(It regularly scores in the Top 10 girls' schools in the country still )

28

We were only taught maths with brackets when I was at school. In fact, we were taught that it was impossible to calculate equations without brackets and that equations didn't make sense without them.

What utter rot!

^ in mathematics and most computer languages, multiplication is granted a higher precedence than addition, and it has been this way since the introduction of modern algebraic notation.[1][2] Thus, the expression 2 + 3 × 4 is interpreted to have the value 2 + (3 × 4) = 14, and not (2 + 3) × 4 = 20. With the introduction of exponents in the 16th and 17th centuries, they were given precedence over both addition and multiplication, and could be placed only as a superscript to the right of their base.[1] Thus 3 + 52 = 28 and 3 × 52 = 75.
These conventions exist to eliminate notational ambiguity, while allowing notation to be as brief as possible. Where it is desired to override the precedence conventions, or even simply to emphasize them, parentheses ( ) can be used to indicate an alternative order of operations (or to simply reinforce the default order of operations)^

https://en.wikipedia.org/wiki/Orderoff_operations

25

13

I’m thoroughly confused. Unless it’s time for tea with bananas and biscuits.

Is there actually an answer or is this a trick question where it depends what maths you use?

Andrew Boswell and he was the postmaster!
Or is that a different puzzle?