A ladder rests against a vertical wall, whose length was found to be $7$m$,$ with which it makes an angle of $45\backslash$deg and on a floor. If a man whose weight is one half that of the ladder climbs it $,$ at what distance along the ladder will he be $,$ when the ladder is about to slip? Take coefficient of friction between the ladder and the wall is $1/3$ and that between the ladder and the floor is $(1)/(2)$