3 ms·
Triple the initial number, add a zero at the end, now halve the resulting number is good enough for my purpose. Brain is surprisingly good at doubling, triplin
by gingabriska 7y ago
Triple the initial number, add a zero at the end, now halve the resulting number is good enough for my purpose.
Brain is surprisingly good at doubling, tripling and halving operations.
And visually added zero is quite easy too.
- etaoins 7y agoThat converts miles to approximate hectometres.
- gingabriska 7y agoIt's within 10% error.
- yholio 7y agoYes, it's within 90%.
- mturmon 7y ago*3, *10, /2 == *15 I think you forgot a /10 at the end? I'm surprised this is faster than adding half of the original number.
- greatpatton 7y agoSo 1 mile equals 15km? and then you wonder why all these units conversion and up with probe crashing on mars.
- mynegation 7y agoIf you are going that route, why not multiply by 8 and divide by 5 for a much better approximation. But to be honest for me it has always been easier to directly multiply by 1.6 (or 1.5 for your case)