Spoiler: Do not watch the video until you've tried the puzzle yourself
A DECEPTIVELY tricky maths problem is currently bamboozling Boltonians on Facebook.
Seen by more than 10,000 people and shared nearly 3,000 times, the sum appears to be a relatively simple matter of addition, subtraction and multiplication.
However, the ‘six sevens problem’ has produced some wildly different solutions, with the most common answer actually being incorrect.
Have a go for yourself and see what answer you come up with, then scroll below to see the correct answer and watch the video explainer.
In truth, it’s a bit of a trick question which relies on how computers like calculators or a spreadsheet would work out the solution.
Computers give the incorrect solution of 56 because they jump to the partial answers after each time any of the +-*/ are pressed
7+7 = 14
/ 7 = 2
+ 7 = 9
* 7 = 63
- 7 = 56
To figure out the correct answer, one must remember ‘BODMAS’ – an acronym to remember the order of operations.
This means anything in brackets in sum must be calculated first, followed by orders (square roots or powers), then division and multiplication and lastly addition and subtraction.
Since the above sum has no brackets, one must skip to the next order, which is division and multiplication.
The correct answer is, in fact, 50, worked out as either:-
50=7+7/7+7*7-7
50=7+ (7/7)+(7*7)-7
Some incorrect answers you may have encountered are:-
0=(7+7)/(7+7)*(7-7)
8=(7+(7/(7+(7*(7-7)))))
56==((((7+7)/7)+7)*7)-7
44=(7+7)/7+(7*7)-7
2=(7+7)/7+7*(7-7)
0.2857=(7+7)/(7+7*7-7)
-6.75=(7+7)/(7+7*7)-
Did you get the answer correct? Let us know how you got on in comments.
Video courtesy of Muscle Productions/Youtube
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