Question Number 116913 by Engr_Jidda last updated on 07/Oct/20
Answered by Lordose last updated on 07/Oct/20
$$\mathrm{a}=\mathrm{7} \\ $$$$\mathrm{7}+\mathrm{9d}=\mathrm{2}\left(\mathrm{7}+\mathrm{d}\right) \\ $$$$\mathrm{7d}=\mathrm{7} \\ $$$$\mathrm{d}=\mathrm{1} \\ $$$$\left.\mathrm{a}\right)\:\mathrm{u}_{\mathrm{19}} =\:\mathrm{7}+\mathrm{18}=\mathrm{25} \\ $$$$\left.\mathrm{b}\right)\:\mathrm{s}_{\mathrm{28}} =\:\mathrm{14}\left\{\mathrm{41}\right\} \\ $$$$\mathrm{s}_{\mathrm{28}} \:=\:\mathrm{574} \\ $$$$\left.\mathrm{c}\right)\:\mathrm{u}_{\mathrm{9}} \:−\:\mathrm{u}_{\mathrm{6}} =\:\mathrm{3d}=\mathrm{3} \\ $$
Commented by Engr_Jidda last updated on 08/Oct/20
$$\mathrm{thank}\:\mathrm{you}\:\mathrm{very}\:\mathrm{much}\:\mathrm{sir}. \\ $$