This is kinda funny — Snopes Rates Biden’s Claim That 2+2=5 As ‘Mostly True’ — but as my brother reminded me recently, 2+2 does equal five for large values of 2.
Not really, of course. 2.4, which rounds down to 2, plus 2.4 = 4.8, which rounds up to 5. But that’s just playing with numbers.
2+2=3 would also be true. 1.6 rounds up to 2, and 1.6 + 1.6 = 3.2, which rounds down to 3. But — again — that’s just playing around, and I suppose it highlights the difference between engineering and mathematics. 2+2=4 in mathematics, but in engineering you would say that 2+2=4 +/- 1.
Reminds me of the old joke about engineers:
Q: “Are all odd numbers prime?”
Mathematician: “3 is prime, 5 is prime, 7 is prime, 9 is not prime — nope, not all odd numbers are prime.”
Physicist: “3 is prime, 5 is prime, 7 is prime, 9 … experimental error, 11 is prime, 13 is prime, yes, they’re all prime.”
Engineer: “3 is prime, 5 is prime, 7 is prime, 9 is prime, 11 is prime…”
Lots of variants, too (programmer: 3 is prime, 3 is prime, 3 is prime..)