No offense, but the square root of 16 is something one learns at a very young age and seems a perfectly appropriate question to distinguish a real person from some automated system. If you forgot then you can figure it out in a second or two. And if you can't figure it out, Google provides the answer in a New York second. It's sort of like having to "phone around" to find out 1 + 1.
wow, so many sensible suggestions, and some great test questions that could fool any old spam bot, or automated spam software.
surely it would better to use one of these that any simpleton like me could answer. and yes i did have to phone round my simpleton friends, some of whom were also deprived of an education in higher mathematics at a very young age, but never mind, it only took three calls.... one not in, one with no idea and one damn genius.
never occurred to me to ask the Google. and as far as im concerned 1 and 1 make 11, that's far as i go with mathematics
but anyway, the question is: why cant a simple yet effective solution be used that accommodates people who are not educated to your standards ....or are we all going to be clones....well?