No need to memorize square roots here. Simply square both sides and it’s clear that 50 < 52.
If x^2 < y^2 then x < y (ignoring negative numbers…).
More generally, these types of “math tricks” are about solving for the answer. Not solving for the parts of the question. It’s a great lessom for life, especially working in software.
Any idea where I can get more English questions like the ones you’ve listed? They’re quite enjoyable! Though some of your translations are a bit off:
> A cube has one of its sides 2cm. The total area of the cube is ...
Pretty sure you mean “surface area”.
I plan to put them into a github repo this month.
Sorry for the translations. I will try to check them again, and maybe to some corrections.
Here's another tiny little nitpick if you want to improve your translation a bit more: In English we don't say "inequation", we say "inequality".