In a blog post, Microsoft employee David Gainer said that when computer users tried to get Excel 2007 to multiply some pairs of numbers and the result was 65,535, Excel would incorrectly display 100,000 as the answer.

Gainer said Excel makes mistakes multiplying 77.1 by 850, 10.2 by 6,425 and 20.4 by 3,212.5, but the program appears to be able to handle 16,383.75 times 4. "Further testing showed a similar phenomenon with 65,536 as well," Gainer wrote Tuesday. He said Excel was actually performing the calculations correctly, but when it comes time to show the answer on the screen, it messes up.

Gainer said the bug is limited to six numbers from 65,534.99999999995 to 65,535, and six numbers from 65,535.99999999995 to 65,536, and that Microsoft is working hard to fix the problem.

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