The difference between successive discounts of $40 \%$ followed by $30 \%$ and $45 \%$ followed by $20 \%$ on the marked price of an article is $Rs.\,12.$ The marked price of the article is (in $Rs.$)

$20 \%$ loss on selling price is what per cent loss on the cost price? (in $\%$)

Mahesh purchased $25\, kg$ of rice at $32$ per $kg$ and $15\, kg$ of rice at $Rs\,.36$ per $kg.$ He mixed the two varieties of rice and sold it at $Rs.\, 40.20$ per $kg.$ What is the percent profit earned?

Ram purchases a chair at $Rs.\, 70$ and spent $Rs$. $17$ on its repair and $50$ paise on cartage. If he sold the chair at $Rs.\, 100$ then his approximate margin of profit in $\%$ will be?

A sells an article to $B$ at a gain of $25 \%, B$ sells it to $C$ at a gain $20 \%$ and $C$ sells it to $D$ at a gain of $10 \% .$ If $D$ pays $Rs.\, 330$ for it, how much did it cost $A?$ (in $Rs.$)

Articles are marked at a price which gives a profit of $25 \%$. After allowing a certain discount the profit reduces to $12\frac{1}{2} \%$. The discount percent is