1. The problem statement, all variables and given/known data Explain why wider slits at the same spacing could produce fringes at the outer edges brighter than some of the fringes nearer the centre. 2. Relevant equations fringe spacing = (lamda x D) / slit separation width of central diffraction fringe = ( 2 x lamda x D ) / aperture width 3. The attempt at a solution I know that as a slit gets wider the amount of diffraction decreases. I also know that as distance away from the central fringe increases the intensity decreases. I can't put these ideas together to work out why there is brighter fringese further away when logic tells me otherwise.