100 children at a Science Center sit down at tables for a break. They order one juice each, and 100 juices are brought to the tables. One juice costs €2.50. One of the students takes out a phone and opens the calculator to work out how much the 100 juices cost in total. But instead of pressing ×, the student accidentally presses ÷. The screen shows: €0.025 The student looks at the result and says: — Is that all they cost? It seems strange, but the number is on the screen, so the student does not check again. Meanwhile, the 100 juices are already on the tables, and the children begin opening them. A few minutes later, the bill arrives: €250 The students look at one another. Someone immediately says there must be a mistake. The student takes out the phone again and checks what happened. But instead of pressing ×, the student had accidentally pressed ÷. One wrong tap had turned a total of €250 into a result of €0.025. And all 100 juices had already been opened. When a calculator gives you a result, is it enough to see a number on the screen — or should you also ask whether the result makes sense and what its order of magnitude is? #sabotage #PISA2025 #education #pisa #pisastudie #MrNumberwise #English #20260910 #0058
