Yeah, this will be so helpful when I’m trying to figure out 20% of 36.23!
Look, move the decimal one to the left, you’ve now got 10%. Double that and you’ve got 20%. How often are y’all trying to find out percentages of nice even numbers like that?
See I love quick and dirty rules to get close enough through estimation for whatever I’m mental mathing, because if I need exact numbers I’m turning to a computation device
20% of 36.23 I’d be going “okay 20% of 10 is 2, 3 10s in 36 so 3x2=6, and 6.23 is pretty close to half 10 and half 2 (from my previous 20% of 10 calculation) is 1 so 20% of 36.23 is slightly more than 7”
36.23% of 20 I’d be going “30% of 10 is 3, 2 10s in 20 so 2x3=6, 6.23% is close to 5 so half of 3 is 1.5, 6+1.5=7.5 so 36.23% of 20 is a bit more than 7.5”
Now which is closer to correct? Ehh I’m not sure I haven’t used a calculator yet, but I’m mental mathing so chances are my estimation got me close enough that I can just round to whichever direction is safer for errors and call it good. Usually I’m mental mathing to figure out splitting a bill, a tip or to double check some machine computed math that looks wrong, and none of those call for perfect precision, just getting close enough that it doesn’t matter
Yeah, this will be so helpful when I’m trying to figure out 20% of 36.23!
Look, move the decimal one to the left, you’ve now got 10%. Double that and you’ve got 20%. How often are y’all trying to find out percentages of nice even numbers like that?
See I love quick and dirty rules to get close enough through estimation for whatever I’m mental mathing, because if I need exact numbers I’m turning to a computation device
20% of 36.23 I’d be going “okay 20% of 10 is 2, 3 10s in 36 so 3x2=6, and 6.23 is pretty close to half 10 and half 2 (from my previous 20% of 10 calculation) is 1 so 20% of 36.23 is slightly more than 7”
36.23% of 20 I’d be going “30% of 10 is 3, 2 10s in 20 so 2x3=6, 6.23% is close to 5 so half of 3 is 1.5, 6+1.5=7.5 so 36.23% of 20 is a bit more than 7.5”
Now which is closer to correct? Ehh I’m not sure I haven’t used a calculator yet, but I’m mental mathing so chances are my estimation got me close enough that I can just round to whichever direction is safer for errors and call it good. Usually I’m mental mathing to figure out splitting a bill, a tip or to double check some machine computed math that looks wrong, and none of those call for perfect precision, just getting close enough that it doesn’t matter
36.23 × 20% = 36.23 × 2 ÷ 10 = 7.246