I earned my engineering degree in the year 1 B.C. (Before Calculators)
and can only approximate so many decimal places on my slide-rule.
And these dang bifocals even make that difficult anymore. :-(
(Actually, they did come out with handheld calculators my senior year.
But $200 was a heckuva lot of money for most students,
and use was taboo in class or for exams.
The little marvels only did basic arithmetic and trig functions,
but they sure were an improvement over wading through
conversion/trig/logarithm tables in a reference book!)
Ain't the internet great.