Sudeep buys two $CDs$ for $Rs.\,380$ and sells one at a loss of $22 \%$ and the other at a gain of $12 \%$. If both the $CDs$ are sold at the same price, then the cost price of two $CDs$ is (in $Rs.$)

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 $Rs.$)

A man buys two chairs for a total cost of $900.$ By selling one for $\frac{4}{5}$ of its cost and the other for $\frac{5}{4}$ of its cost, he makes a profit of $90$ on the whole transaction. The cost of the lower priced chair is (in $Rs.$)

A man buys $100\, kg$ of sugar for $Rs.\, 2400 .$ He sold $1 / 4$ th of the stock at a loss of $5 \% .$ At what per cent profit should he sell the remaining stock so as to make an overall profit of $20 \%$ on the whole transaction? (in $\%$)

In these questions, two equations mabered $I$ and $II$ are given. You have to solve both the equations and mark the appropriate option.

$I$. $x^{2}=16$

$II$.$2 y^{2}-17 y+36=0$

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