India, May 18 -- Brain teasers have become a go-to mental workout for people of all ages, especially on social media platforms where they circulate widely. These puzzles not only offer entertainment but also help sharpen memory, boost problem-solving skills, and keep the brain agile. In an increasingly digital world filled with passive scrolling, such challenges encourage active thinking and stimulate the mind in fun, engaging ways.

A brain teaser that surfaced on Facebook is doing exactly that. The image shows a simple addition problem with a twist-one digit is missing. The setup looks like this: 5 6 9 + 1 ? 5 = 7 0 4

Viewers are challenged to figure out what number should replace the question mark to make the equation correct. While i...