Only those with the 'highest visual acuity' can spot odd number in sea of 9s
Yes, your eyes are playing tricks on you. Brain teasers and optical illusions are designed to test your focus and get you to think outside the box by forcing your brain and eyes to work together.
Take a look at the image below and you might think your brain is playing tricks on you, and that's because it kind of is.
In the image your brain will be distracted by the sea of number nines - but don't be fooled. It's only trying to distract you from finding the real thing you're looking for - number six.
Optical illusions are regarded as one of the simplest ways to determine a person's intelligence, based on how easy they find the task. In this case, if you manage to spot the odd number without getting distracted, you have sharp eyesight and high 'visual acuity', according to Jagran Josh.
What makes this challenge even harder is that you only have four seconds to find it - this will really put your observational skills to the test. So, put a timer on and then try to scan each area of the image carefully.
Mind-bending optical illusion makes your brain 'adjust' after 10 secondsIf you don't manage to spot the number six within the time limit, don't worry too much. This one really is tricky, as the number six and nine are so similar - but don't be discouraged.
Do you give up? First, glance over the image again, but this time focus your attention on the bottom right hand side of the image. This is where you'll find that pesky number. If your patience has run out, take a look at the answer below.
There's no such thing as completing too many mental puzzles, so why not have another go? In a separate puzzle, you're challenged to find the lipstick hiding among the perfume bottles.
Another puzzle challenges you to spot five specific items within an image of three people and a dog. If you can find them within 15 seconds you're deemed a 'genius'. Alternatively, you could try and find out your worst personality traits with this optical illusion.
Did you manage to find the number six? Let us know in the comment section below.