Some. Close enough to get a rough idea.
2/5 x centimeters equals inches.
2/3 x kilometers equals miles.
I can't convert grams to oz very easily, but I have a gram scale, and I know 28.35 g equals 1 oz, but I can't do that in my head.
Centigrade to Fahrenheit always puzzled me, but someone online said double it and add 30. That's close enough for me.
18° c = 66°F close. Actual 66.4°F.
Tump is legally crazy enough to win an insanity plea?