An article is marked for sale at $Rs. 504$. The shopkeeper gives a discount of $5\%$ on the marked price and still earns a profit of $20\%$. What is the cost price of the article? (in $Rs.$)

$A$ dealer sold two types of goods for $Rs. 10,000$ each. On one of them,he lost $20 \%$ and on the other he gained $20 \%$. His gain or loss per cent in the entire transaction was

$A$ man sold a cow at a loss of $12 \%$. If he had sold it at a gain of $6 \%$,he would have received $₹ 72$ more. What was the cost price of the cow?

$A$ vendor bought toffees at $6$ for a rupee. How many for a rupee must he sell to gain $20 \%$?

$A$ person earns $15 \%$ on an investment but loses $10 \%$ on another investment. If the ratio of the two investments is $3:5$,what is the gain or loss percentage on the two investments taken together (in $\%$)?

Ram sells an article to Girish at a gain of $20 \%$,Girish sells it to Sanjay at a gain of $10 \%$,and Sanjay sells it to Aditya at a gain of $12 \frac{1}{2} \%$. If Aditya pays $Rs. 59.40$,what did it cost Ram in $Rs.$?