A deceptively simple children's brainteaser is sweeping the internet as adults struggle to work out the correct answer.
The perplexing puzzle, based around a basic mathematical equation using a range of fruits, asks you to decipher which number each fruit symbolizes, similar to algebra, then work out the total.
But the apples, bananas and coconuts appear to be leaving adults completely flummoxed.
The first sum shows that three apples added together amounts to 30, suggesting that one apple is equal to the number 10.
On the second line, it states that one apple (10) plus two bunches of bananas equals 18, which seems to imply that each bunch of bananas is equal to 4.
The next line states that a bunch of bananas (equivalent to 4) minus a coconut equals 2- suggesting that a coconut is equivalent to the number 2.
On the final line, it asks you to guess the total of half a coconut (1), an apple (10) and a bunch of bananas (4).
A quick glance at the puzzle might suggest the answer is 15, however people trying their hand online were coming up with a plethora of different answers.
Some people failed to spot that the first bunch has four bananas, left, while the final bunch has just three, right
Not all coconuts are created equal: One was made up of two halves, left, while one was made up of just one
One Facebook user stated that the correct answer should be 14, seeing as the bunch of bananas on the final line in fact symbolized 3, rather than 4.
Indeed, on closer inspection there are just 3 bananas in the final bunch, and 4 in the rest.
Paul Blanch wrote: '16 - easy! 3 apples = 30; therefore apples are worth 10 Apple - 2 bananas = 18; the apple is worth 10, so the bananas are worth 4. Banana - coconut = 2; the banana is worth 4, so the coconut is worth 2. The last line? Coconut (2) +apple (10) +banana (4) =16.'
Another user wrote: 'Its very simple, and the answer is 16. Each apple stands for 10, while each banana stands for 4 and each coconut stands for 2. You now have the answer.'
Obaidullah Khan Barcha said: 'On second and third line there are 4 bananas in a bunch but in the last line there are only 3 bananas in a bunch, that's why the answer is 15.'
Ethan Pearson agreedm saying: ' There is only 3 bananas in the last equation so it equals=15Apple=10, Apple+Apple+Apple=30Banana=4, Apple+Banana+ Banana=18.
'Coconut=2, Banana-Coconut=2Banana=3Coconut+Apple+3 Bananas=15. Answer is = 15.'
Perplexingly, one man came to the conclusion that the answer was 20. He commented: '1 apple equals 10, coconut equals 6 and banana bunch equals 4 so your answer is 20.'
Dr Kevin Bowman, professor of mathematics, said: ‘You can interpret it in many ways; one way is no more correct than another.
‘There’s no ambiguity in the first equation; 3 apples is 30, so one apple is worth 10.
'But because all the bananas aren’t the same, you could say that they all represent different amounts.
‘You might even say that the two coconut pieces in the third equation are different sizes, and therefore add up to three quarters or even seven eighths when put together.
‘In that sense, there are an infinite number of possible answers.' People are torn over whether the correct answer is 14, 15, 16 or even 20.
(I don't know about you but my head is spinning and I am going to get some aspirin.)
This isn't the first mind-bending puzzle to sweep the internet in recent months. Earlier this year, National Geographic's puzzle asking you to identify which direction a bus is travelling in left thousands of adults scratching their heads.
Their version of the popular puzzle showed a yellow bus with identical windows at either end - giving no clue as to which is the front or back of the bus. The correct answer is that - if you're in the UK - the bus is travelling to the right. And the key to solving the puzzle is the fact that you can't see the passenger doors. However in North America, you would be driving on the right side of the road, therefore you would be going left.
Which direction is the bus travelling in? National Geographic's version of a popular logic puzzle for their Brain Games TV series went viral earlier this month, but it often proves too much of a challenge for adults
There it is! Gergely Dudás' elusive panda is hidden in amongst hundreds of festive snowman; eighth row from the top, fourth from the right. The picture went viral in December with thousands of people sharing it online.
In December, an illustration featuring a hidden panda left thousands of people flummoxed as it swept social media. Hungarian artist Gergely Dudás posted the Christmas puzzle on his Facebook page on December 16th, showing hundreds of hand-drawn snowmen with the single black and white bear hidden among them.
I guess we are geared to problem solving. We also like challenges. Our fascination with puzzles give us the satisfaction we are seeking. It is also a great way to keep your mental faculties sharp. Sadly, mine weren't too sharp to begin with.