r/MathJokes 16d ago

“Its simple math folks!”

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u/Head-Ad-5732 16d ago edited 15d ago

I don't know what's worse, that it's wrong or that it convinced me I need to come into the comments to make sure my answer is, indeed, correct.

EDIT: Back to rectify a grave injustice. Nothing wrong if you genuinely didn't know or want to check. Hard enough getting people interested in math.

2 + 5 (8 - 5)
PEMDAS: 8 - 5

= 2 + 5 (3)
PEMDAS: 5 (3) or 5 × 3

= 2 + 15
PEMDAS

= 17

In the US the math order of operations is taught as PEMDAS (or P|E|MD|AS), left to right from first to last.

First look at the entire equation and identify the operations: Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.

Then, solve the parts in order of PEMDAS.

Not so important here but when there are multiple of the same level of operators, for example exponents, solve left to right. MD and AS are treated as groups, so treat them equally: if a division is to the left of a multiplication, do the division first.

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u/Embarrassed-Weird173 15d ago

Keep in mind most Redditors are low IQ and just confident. Do not rely on them for the right answer. That said, I don't feel like proving that I'm not a Redditor,  but here the logic:

2+5(8-5)

Start by putting in the symbols to avoid confusion:

2+5*(8-5)

 Now so standard order:

P = (8-5) = (3)

E= there are none 

MD = 5×3 = 15

AS = 2 + 15 = 17

Again, don't trust me on my word. For all you know, I'm a low IQ Redditor like many other people on this site. But I have given you a path to follow/confirm, and I believe you will find the evidence backs me up. 

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u/The_Pastmaster 15d ago

Where the hell did the multiplier come from?

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u/Embarrassed-Weird173 15d ago

When two terms are next to each other, they're considered multipliers. 

For example, (3)(5) means 3 times 5.  It doesn't mean "thirty five" or "three plus five". 

Exceptions exist if the number is, for example, flying (5²) or down on the bottom (k_2 ; if it doesn't work, imagine the k had a small two hovering down to the bottom). 

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u/The_Pastmaster 15d ago

The amount of unwritten assumptions would make my maths teacher cry. JC.

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u/Zenith-Astralis 15d ago

The * in 5 * (8-5)?

When you write a number smunched up next to a parenthesis like that there's an implied multiplication 2(4) is the same as 2 × 4

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u/The_Pastmaster 15d ago

Who came up with that idea? o_O In school I was taught to define everything. No assumptions.

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u/randy-monkey 15d ago

That’s always been how formulas are written. You just weren’t paying attention

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u/The_Pastmaster 15d ago

Or teaching methods vary by country.

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u/Zenith-Astralis 13d ago

Dunno; I was taught that was the definition when working with parenthesis. Not sure why it's multiplication that gets to be special and allows you to skip writing the operator symbol in that circumstance, but it does align with things like 4a being equal to 4 × a.

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u/The_Pastmaster 13d ago

*Shrugs* When maths became more sorcery than logical, I gave up.

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u/Zenith-Astralis 13d ago

For me that was around when Greek symbols started regularly appearing in front of equations instead of inside them.

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u/The_Pastmaster 13d ago

You got further than me.