Overview

• The latest viral challenge, “(100 ÷ 2)(7 − 5) × 1 + 100,” has reignited discussions by hiding a multiplication step between adjacent parentheses.
• Step-by-step solutions show that resolving the parentheses yields (50)(2) × 1 + 100, which evaluates to 200 when multiplication and addition follow in order.
• Reporters stress that applying order-of-operations rules—PEMDAS or BODMAS—correctly is essential to avoid common errors in mixed arithmetic puzzles.
• A Princeton University study published in the Journal of Neuroscience reveals that routine mental math engages brain regions linked to logic, reasoning and decision-making.
• Cognitive research indicates that daily calculation exercises can enhance memory, focus and creativity, lower stress and help stave off cognitive decline.