By what fraction selling price $(S.P.)$ must be multiplied to get the cost price $(C.P.)$ if the loss is $20 \%$?

The marked price of a watch was $Rs. 720$. $A$ man bought the same for $Rs. 550.80$ after getting two successive discounts,the first being $10 \%$. The second discount rate is.......$\%$

$A$ man buys an article for $Rs. 27.50$ and sells it for $Rs. 28.60$. Find the gain percent. (in $\%$)

There is a profit of $20 \%$ on the cost price of an article. The per cent of profit, when calculated on the selling price is.......$\%$

Sardar Singh bought $200$ dozen oranges at $Rs. 10$ a dozen. He spent $₹500$ on transportation. He sold them at $Rs. 1$ each. What was his profit or loss percent?

$A$ loss of $19 \%$ gets converted into a profit of $17 \%$ when the selling price is increased by $Rs. 162$. The cost price of the article is (in $Rs.$)