2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/45285Consequences of the interference between external and internal spectator amplitudes for the lifetimes and semileptonic decay fractions of $B^0$ and $B^+$ mesons are discussed. Extrapolating from the constructive interference observed in 11 exclusive hadronic $B$ decays we find an inclusive semileptonic decay fraction of $(11.2 \pm 0.5 \pm 1.7)$\%, significantly closer to the experimental results than previous predictions.3pages Latex, ICHEP.STY includedHigh Energy Physics - Phenomenologytext