What is 8÷2(2+2)? This simple math equation posted by @pjmdoll on twitter has the whole internet divided!
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You get 10 seconds to solve this puzzle. Pause the video if you need more time.
If your answer is either 1 or 16 then you may now join the debate!
Many cannot agree on the answer and even those that have math degrees have weighed in on the subject siding with one answer over another.
Central to the issue is the rule for order of operations BEDMAS, which stands for brackets, exponents, division, multiplication, addition and subtraction and how it is applied to the equation.
Let's solve this by strictly adhering to the BEDMAS rule: - First, we calculate the bracketed part first (2+2) which is 4. - Then we divide 8 by 2 which yields 4. - Finally we multiply 4 and 4 together to get 16.
So how are people getting an answer of 1?
I believe the confusion arises in the division operation being represented by one symbol (whether it be an obelus or a slash). Division represented by one symbol is often used in elementary school, math skill testing questions on sweepstakes and programming. The fraction bar (numerator over denominator format) is heavily favoured beyond elementary school and is much less ambiguous.
Going back to the equation. If we convert this problem using the fraction bar, there will be 2 ways this can be conceptualized:
1) On the left hand side we have 8 over 2(2+2) 2) and on the right hand side we get 8 over 2 times (2+2).
And this is exactly where the source of the confusion arises!
Solving these in parallel, 2+2 becomes for both sides. The left side becomes 8 over 4*2 and the right becomes 4 times 4, which then gets us to our 2 answers 1 and 16.
On a side note: Feeding "8/2(2+2)" into google and wolfram alpha (a popular math tool) we get ..