CPA's always try to make sure everything cross-foots. They continually review their number crunching for accuracy to make certain it totals to the penny. Engineers on the other hand will not hesitate to approximate, if expedient, although they too try to be right on target. To them, mathematics is the “language of science.”

Yet Salesmen still lean towards arithmetic being an integral part of their very well-developed art of persuasion. They are far more flexible in using creativity to guarantee that their always "correct" answers ultimately result in helping them  “make the sale!”

Mildred Hado's 1973 Painting Entitled "Men And Their Numbers"

Now just how much is two plus two?
The Answer may depend on you!
Accountants, quite precise, should show,
That 2 + 2 is 4 point 0!

Yet Engineers whose Math is fine,
Will swear it’s three point nine nine nine!
Still neither one could misconstrue,
Which Total’s best or which one's true!

But Salesmen take a different View,
When calculating two plus two;
They'll smile, then ask each Prospect, "Gee,"

“What would you like your Sum to be?”