Overview
- A string of quick arithmetic challenges ran across outlets from Friday through Sunday, with publishers posing time‑limited puzzles and then posting full solutions to show the correct method.
- The most recent puzzle published Sunday by Los Andes presented (30 × 5 + 60) ÷ (15 + 15) and gave the correct result as 7.
- Earlier items included (18+6) ÷ 3 × 2 − 5 = 11, 40 − (12+8) ÷ 4 × 3 = 25 and (6.000 × 4 + 16.000) ÷ (3 + 1) = 10.000, each solved step by step to illustrate PEMDAS.
- Articles repeatedly flag common errors such as ignoring parentheses or mishandling left‑to‑right rules for multiplication and division and they explain the correct sequence: parentheses, exponents, multiply/divide left to right, add/subtract left to right.
- Publishers frame the puzzles as short cognitive exercises and cite research on cognitive reserve to suggest mild mental benefit, but the pieces present the items mainly as informal teaching and reader engagement rather than scientific interventions.