Find $CP$ when $SP = Rs.\, 51 .70, \operatorname{loss}=12 \% ?$

The cost price of a table is $Rs.\,3,200.$ A merchant wants to make $25 \%$ profit by selling it. At the time of sale he declares a discount of $20 \%$ on the marked price. The marked price (in $Rs.$) is

A man bought orange at the rate of $8$ for $Rs.\,34$ and sold them at the rate of $12$ for $Rs.\,57.$ How many oranges should be sold to earn a net profit of $Rs.\,45?$

A trader sells his table at a profit of $15 \%$ and the chair at a loss of $7 \frac{1}{2} \%,$ but on the whole he gains $Rs.\, 50 .$ If he sells the table at a loss of $7 \frac{1}{2} \%,$ and chair at a profit of $15 \%,$ then he neither gains nor loses. Find the cost price of the table

If the cost price of $12$ pens is equal to selling price of $8$ pens, find the gain percent.

Two items $A$ and $B$ are sold at a profit of $10 \%$ and $15 \%,$ respectively. If the amount of profit received is the same, then the cost price of $A$ and $B$ may be (in $Rs.$)