C-14-Q152mediumsingle_mcqa:b=c:da:b=c:da:b=c:d হলে ac=?\dfrac{a}{c}=?ca=?abd\dfrac{b}{d}dbbdb\dfrac{d}{b}bdcadbc\dfrac{ad}{bc}bcadda+bc+d\dfrac{a+b}{c+d}c+da+b