this post was submitted on 03 Dec 2023
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Left to right. If you’re following ALL of the rules of PEMDAS then the answer is 16
...1. If you got 16 then there's one or more rules that you didn't obey.
Multiplication before division bro.
The division goes last.
Answer is 1.
The answer is 1, but the logic you've used to get there is a little off. Different groups actually follow different logic, but they usually arrive at the same end-point.
The American Mathematical Society goes:
While the American Physical Society does
In both cases, addition and subtraction are equal in priority (this solves the problem brought up by a different comment where following primary school BIDMAS would mean 8-4+2=2). In one case (and this is the way I prefer to do it) they solve the problem by declaring that implicit multiplication is done before division, but explicit multiplication with the × sign follows the same rules you would have learnt in primary school. The other says all multiplication is done before division, including explicit multiplication.
It's never that - that's how people are getting the wrong answer. In high school you get taught about The Distributive Law.
Multiplication and division have the same priority, whichever one comes first LTR is the one that gets resolved first, so it's (8 / 2) * 4
It's 8/2(2+2)=8/(4+4) or 8/2(2+2)=8/2(4)=8/(2x4)
By that logic: 8-2+4=2
Of course, it could be kind of ambiguous, but typical convention gives multiplication/division the same priority, as it does addition/subtraction.
And in general, you need to go left to right when dealing with division and subtraction, if other operations have the same priority.
Right answer but wrong reason. It's because distribution comes first