2 ms·
Speaking of which, I want to warn everyone that I've found that Wolfram Alpha is not always mathematically precise! Here is an easy and concerning way you can
by upwardbound 4y ago
Speaking of which, I want to warn everyone that I've found that Wolfram Alpha is not always mathematically precise! Here is an easy and concerning way you can repro this:
I noticed that if you put this formula into WolframAlpha, it gives a wrong answer.
Input: 1’ 1” x 7’ 2.5”
Primary result: 1125 sq inch (correct)
Secondary result: 7.809 sq ft (WRONG)
The correct sq ft is 7.8125 (exact) or 7.813 (rounded)
Bug link:
https://www.wolframalpha.com/input?i2d=true&i=1%E2%80%99+1%E2%80%9D+x+7%E2%80%99+2.5%E2%80%9D https://www.wolframalpha.com/input?i2d=true&i=1%E2%80%99+1%E...
- eesmith 4y agoIt looks like a rounding difference in the display. The exact answer is 1124.5, which when rounded up to 4 significant digits is 1125 sq inch. 7.809 sq ft is the correct answer in sq ft, again, rounded to 4 significant digits. >>> (1*12 + 1 ) * (7*12 + 2.5) 1124.5 >>> ((1*12 + 1 ) * (7*12 + 2.5) ) / (12 * 12) 7.809027777777778 This is the decimal display of the closest float64 value to the exact rational answer of 2249/288 sq. ft (7 and 233/288 sq. ft., or 7 sq. ft. and 116.5 sq. inches).