We have several MP25DV-3 desktop calculators in our office and one of them keeps randomly miscalculating. Each time it happens we zero it out and enter the same formula, but sometimes it will print out the wrong numbers.
Twice it has happened where it changed its mind by .01. On those occasions we chalked it up to a rounding error, even if it was strange that it wasn't rounding the same way every time.
Today it happened with a large error. 122 x 0.74 = 33.61 and then when we tried again because that was obviously wrong it did 122 x 0.74 = 90.28.
We have it set to print out all calculations on a tape, so we have the tapes showing the error. From the tape we are able to doublecheck that we didn't accidentally enter a wrong number.
Can anyone think of some human error that could cause something like this? Is there a bug in the software that could be causing this? We are mystified and worried about what other calculation errors it could be producing that we don't notice.
