In the digital era, when material travels like wildfire, it’s unsurprising that a basic math brain teaser has gone viral. The $100 problem, which asks players to calculate how much money a business lost when a robber took $100 cash and subsequently made a purchase, has garnered millions of views and stirred heated debate among puzzle fans.

An account named Out of Context Human Race shared the brain teaser on X (formerly Twitter), depicting a simple scenario. A guy takes $100 from a store’s register and then uses it to purchase $70 worth of products, earning $30 as change. The issue then becomes, “How much money did the store lose?”.

As the brain teaser gained popularity online, the comments area overflowed with answers. Some people firmly asserted that the business lost $100, but others contended that the net loss was $130, including the stolen $100 plus the $30 in change. Some even asserted that the individual transaction profit margins determined the store’s total loss.