TITLE: calculus textbook avoiding "nice" numbers: all numbers are decimals with 2 or 3 sig figs
QUESTION [6 upvotes]: Many years ago, my father had a large number of older used textbooks.
I seem to remember a calculus textbook with a somewhat unusual feature, and I am wondering if the description rings a bell with anyone here.
Basically, this was a calculus textbook that took the slightly unusual route of avoiding "nice" numbers in all examples. The reader was supposed to always have a calculator at their side, and evaluate everything as a decimal, and only use 2 or 3 significant figures.
So for instance, rather than asking for the $\int_1^{\sqrt3} \frac{1}{1+x^2}$, it might be from $x=1.2$ to $x=2.6$, say.
The author had done this as a deliberate choice, since most "real-life" math problems involve random-looking decimal numbers, and not very many significant digits.
Does this sound familiar to anybody? Any ideas what this textbook might have been?

REPLY [5 votes]: Though this is probably not the book you are thinking of, Calculus for the Practical Man by Thompson does this. It is, most famously, the book that Richard Feynman learned calculus from, and was part of a whole series of math books "for the practical man". The reason I do not think it is the particular book you are thinking of is that the most recent edition was published in 1946, so there would be no mention of a calculator.