Lets try (1/11) + (10/11) First fraction is 0.090909(09)r, Second fraction is 0.909090(90)r Sum of fractions is 0.999999(99)r A little re-org on the original expression (1 + 10)/11 yields 11/11 is 1 Did I miss part of this thread? Regards, Dave Bob Ammerman wrote: > > All repeating numbers are rational. There is a relatively simple proof of > this. > > Given a number N which ends in a repeating group of 'p' digits: > > Then the number (10^p) * N ends with the same repeating block. > > Now if we subtract: > > (10^p)*N - N > > the 'repeating blocks' cancel out and we have a terminating decimal (the > part of N before the repeating block). Note, of course that this terminating > decimal is rational. > > Thus, N(10^p-1) == N(10^p-1) is rational. If we now divide this by (10^p-1) > we have: > > N(10^p-1) > N == ------------------- > 10^p-1 > > Note that both the numerator and denominator are rational, therefore the > entire value is rational, therefore N is rational. > > By the way: this proof is from my 11th grade trigonometry book. > > Bob Ammerman > RAm Systems > (contract development of high performance, high function, low-level > software) > > -- > http://www.piclist.com hint: The PICList is archived three different > ways. See http://www.piclist.com/#archives for details. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.