CASIO fx-991CW

[lrdheat]

Was wondering why the U.S. version does not have the product operation, but then realized that I could use summation of logs from x to y, and then take the anti log of the answer. This can also be used to find factorials greater than 69! by using integer number part of the logarithm as power of 10 of the answer (if log was used), and raising 10 to the decimal part of the logarithm to find the part of the answer that is the number times the power of 10.