And you, did you find it on the first try?
No judgment here! Whether you found 22 immediately or not, the important thing is to understand the mechanism behind the mistake.
With a little attention and keeping this rule in mind, you will no longer be trapped by this kind of calculation.
And the next time you come across a "too easy" operation, you'll know that it might deserve a second look.
Sometimes, the simplest things teach us the most.
