If “close enough” works, then it’s nice to have the skill. Having the skill requires occasionally using it.
Where accuracy is important, since we almost always have a calculator with us now, that’s a no-brainer.
Maybe more to the point, though, understanding how percentages work is wise. It’s one of the few arithmetic topics that we encounter regularly in life.
In this case, 23% of 53 and 53% of 23 each have their own little trick, depending whether you’d rather overestimate a little with 1/4 of 52 or underestimate a little with half of 24. I find it handy to be able to think that way, especially for example when trying to get out of a taxi and paying cash.
If “close enough” works, then it’s nice to have the skill. Having the skill requires occasionally using it.
Where accuracy is important, since we almost always have a calculator with us now, that’s a no-brainer.
Maybe more to the point, though, understanding how percentages work is wise. It’s one of the few arithmetic topics that we encounter regularly in life.
In this case, 23% of 53 and 53% of 23 each have their own little trick, depending whether you’d rather overestimate a little with 1/4 of 52 or underestimate a little with half of 24. I find it handy to be able to think that way, especially for example when trying to get out of a taxi and paying cash.