Measurements of the absolute branching fractions of B-+/--> K-+/- Xc(c)over-bar-$

We study the two-body decays of B+/- mesons to K+/- and a charmonium state X-c(c) over bar in a sample of 210.5 fb(-1) of data from the BABAR experiment. We perform measurements of absolute branching fractions B(B+/- -> K+/-Xc(c) over bar) using a missing mass technique, and report several new or improved results. In particular, the upper limit B(B+/- -> K+/-X(3872)) < 3.2 x 10(-4) at 90% C.L. and the inferred lower limit B(X(3872) -> J/psi pi(+)pi(-)) > 4.2% will help in understanding the nature of the recently discovered X(3872).