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Optical illusions are always fun to look at, but they are also a cool way to test how sharp you are. Whether it is a hidden number, a colour trick, or a spot-the-difference challenge, our brains love ...

Do you love a brain-storming optical illusion? Today’s viral brain teaser dares you to do just that: find the numbers 54 and 55 hidden in a confusing sea full of 45s. And the challenging part is, you ...