A picture circulating online challenged people to determine the missing number from what looked like a simple sequence of numbers from 1 to 19. "Which number is missing?" the puzzle asks.

A popular online math puzzle involves finding a missing number in triangles by using a simple addition rule. Engaging with such puzzles strengthens cognitive skills and problem-solving abilities ...

Puzzles9 shared a brain teaser with nine squares, one missing a number. The challenge is to figure out how the numbers are related and fill in the missing one. Can you solve it?