“It is indeed,” replied the person with black hair. “And have you noticed that not one of us has hair that matches his or her name?” “By golly, you’re right!” exclaimed Professor White.

If you think you are an expert puzzle solver, then test your IQ and problem-solving skills by solving this viral math puzzle, which only 3% of geniuses with high IQ can solve in 7 seconds. Can you?

Black dot puzzle: Why you can’t see all the black dots in this picture JUST when you think you have your life together, the internet throws you an optical illusion that makes your head hurt.

These pictures are black and white but coloured grids make us think otherwise (Picture: Øyvind Kolås ) The internet is fascinated with how we each see things – be that the dress or the shoes.

Solve the Spider-Man PS4 Yin and Yang puzzle. Revolve the black and white dials and open the hidden doorway with this handy guide.