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SKIP KILPATRICK
01-26-2018, 09:25 AM
Arithmetic problem:

Solve for X

9 – 3 ÷ 1/3 + 1 = X

Keith Wilson
01-26-2018, 09:28 AM
X=1 (at least if you assume that 1/3 is a number, not a division operation)

StevenBauer
01-26-2018, 09:28 AM
Order of operations: 1

SKIP KILPATRICK
01-26-2018, 09:33 AM
correct. I screwed it up the first time solving from left to right.

I've been out of school too long.

PEMDAS rule—'Please Excuse My Dear Aunt Sally,' or 'Parenthesis, Exponents, Multiplication, Division, Addition, Subtraction'

jackster
01-26-2018, 09:50 AM
Mmmmm. Lets see.... 9-3 is 6. 6 divided by 1/3(.33333) is 2. 2 plus 1 is...4. NoNoNo
9-3 is 6. 1/3 plus 1 is...1 1/3. 6 divided by 1 1/3 is....4.5. NoNoNo
9-3 is 6. 6 divided by 1/3(.3333) is 18. 18 plus 1 is... 19. NONONO!
9 - ...3 divided by 1/3(.333) plus 1 which is 9. so.. 9-9 is 0. NONoNONo!!
I give up!! :confused:

beernd
01-26-2018, 09:55 AM
x=1
As Keith said if 1/3 is a number

Keith Wilson
01-26-2018, 10:02 AM
If there are no parentheses and 1/3 is a number, multiplication and division first, addition and subtraction afterwards. Thus:
9 - (3÷(1/3)) + 1
9-9+1
1

amish rob
01-26-2018, 10:14 AM
42!

Peace,
Math Magician

sharpiefan
01-26-2018, 10:35 AM
6 Deceptively Simple Maths Problems That No One Can Solve (ARTICLE LINK) (https://www.sciencealert.com/6-simple-maths-problem-that-no-one-can-solve)

Excerpt
We all know that maths is really hard. So hard, in fact, that there's literally a whole Wikipedia page dedicated to unsolved mathematical problems, despite some of the greatest minds in the world working on them around the clock.

But as Avery Thompson points out at Popular Mechanics, from the outset at least, some of these problems seem surprisingly simple - so simple, in fact, that anyone with some basic maths knowledge can understand them... including us. Unfortunately, it turns out that proving them is a little harder.

Inspired by Thompson's list, we've come up with our own list of deceptively simple maths problems to frustrate (and hopefully inspire) you.

#include [std-disclaimer]

David G
01-26-2018, 10:49 AM
Yes - x=1 is how I'd solve it as well.

As an aside - Because it has a variable... I'd call this an algebra problem, not just arithmetic.

Why such a simple equation, though. You figured adding exponents & parentheses would totally throw us? Or is there some tricky bit I've skipped over?

CWSmith
01-26-2018, 11:03 AM
Order of operations: 1

That's the way I see it. Bad programming style, by the way.

Ian McColgin
01-26-2018, 11:44 AM
I hate operations with no parentheses. One of the sad by-products of using modern calculators.
hout
If you do it as written solving each step as you go:

9 - 3 = 6

6 / 1/3 = (6)(3)/1 = 18

18 + 1 = 19

This is the same as [(9 - 6)/(1/3)] + 1

But if you sum the first three in one step by calculator you get -9.02 and 1 to that for -8

while if you do all three by calulator, adding on each step without hitting =, you get 1.

All of which is why it's wrong not to use the parentheses to show the order.

Tom Wilkinson
01-26-2018, 12:04 PM
The order of operation doesn't require parentheses. The issue here is what the 1/3 represents. As written the answer should be 9. In order for the 1/3 to represent a number it would have to be in parentheses for the order of operations to allow it to be done first. The ÷ and / sign mean exactly the same thing so you cannot make the assumption that 1/3=.33333.......
You have to do 3 ÷ 3 ÷ 1 since that is the order of operation left to right. Pemdas. There are no parentheses so the 1/3 is not automatically considered .33333...

If you do it as written with a scientific calculator you will get 9.

9 – 3 ÷ 1/3 + 1 = X

9 - 3 / 1 / 3 +1= X

9 - 3/1 ÷ 3 +1=X

9-3 ÷ 1 ÷ 3 + 1 = X

Edit, the proofs indicate that this is incorrect, and 1 is the correct answer, but I'm unclear as to why the 1/3 is treated as a fraction when not in parentheses. Anyone able to explain that?

All the same.

Too Little Time
01-26-2018, 12:14 PM
A simple cut and paste into the the address bar of a browser produces some result. If I took the time to do so, I would know the answer.

I just had to do it. Oh. My. My mistake. But it does seem a number of people have produced produced a result that is inconsistent with the math logic of my browser.

Rum_Pirate
01-26-2018, 01:13 PM
Arithmetic problem:

Solve for X

9 – 3 ÷ 1/3 + 1 = X

parenthesis, exponents, multiplication, division, addition, subtraction.

9 - (3 ÷ 1/3) + 1
9 - 9 + 1
0 + 1
1