Explanation
Let the cost price $$=Rs100$$
Then, including tax $$=100+\dfrac{11}{100}=110\%$$
So,
$$110\%$$ of S.P $$=Rs\,616$$
Then,
$$ S.P=\dfrac{616}{110}\times 100 $$
$$ S.P=Rs\,560 $$
Now, Cost price of $$12\%$$ $$=\dfrac{100\times560}{100+12}=\dfrac{100\times 560}{112}$$
$$=Rs\,500$$
Please disable the adBlock and continue. Thank you.