Many mistakes in such tasks do not arise from a lack of arithmetic skills. Often, people simply start too quickly.
Anyone who takes a few seconds to look at the entire printout can clearly see the individual components:
- two multiplications,
- an addition,
- a faculty.
Only after these components have been identified should the actual calculation begin.
This is also why very short tasks sometimes generate a surprisingly large number of comments and different solutions. The simpler a task appears, the greater the temptation to solve it mentally without careful reading.
Is 16 correct or incorrect?
According to the usual mathematical rules, the answer is clear: 16 is correct.
The statement in the image that the answer is « NOT 16 » contradicts the result of the depicted mathematical expression. If no additional rule, further context, or other definition is provided, the standard mathematical interpretation remains valid.
The calculation is therefore:
2 × 2 + 2 × 3! = 16
The real trap of the puzzle
The most interesting trap, therefore, may not lie in the mathematics itself, but in the wording of the problem. It attempts to sow doubt about an obvious and, at the same time, correct solution.
Someone who receives 16 and then reads the sentence « The answer is NOT 16! » might start calculating again, looking for a mistake that doesn’t even exist.
This makes this little puzzle a good example of how strongly a given statement can influence our expectations.
Conclusion
The puzzle 2 × 2 + 2 × 3! initially appears inconspicuous, but contains the factorial symbol, a detail that absolutely must be taken into account.
First, 3! is calculated as 3 × 2 × 1 = 6. Then the multiplications follow: 2 × 2 = 4 and 2 × 6 = 12. Finally, both results are added.
4 + 12 = 16.
This means that the answer excluded in the image is, in fact, the correct one according to standard mathematical rules. The real puzzle, therefore, lies not only in being able to calculate, but also in not being misled by the provocative title.
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