Albert buys $4$ $horses$ and $9$ cows for $Rs. 13400$. If he sells the horse at $10 \%$ profit and the cows at $20 \%$ profit, then he earns a total profit of $Rs.\, 1880 .$ The cost of a horse is (in $Rs.$)

Charging $30 \%$ above its production cost a radio maker puts a label of $Rs.\, 286$ on a ratio as its price. But at the time of selling it, he allows $10 \%$ discount on the labeled price. What will his gain be? (in $Rs.$)

A trader buys $500\, kg$ of cotton for $Rs.\, 9,000.10 \%$ of this cotton is spoiled due to rain. At what rate ($Rs./ kg$) should he sell the rest to earn $10 \%$ profit?

A discount of $15 \%$ on one article is the same as a discount of $20 \%$ on another article. The costs of the two articles can be (in $Rs.$)

A shopkeeper sold Chairs at $Rs.\, 2139$ each after giving $7 \%$ discount on labelled price. Had he not given the discount, he would have earned a profit of $15 \%$ on the cost price. What was the cost price of each chairs? (in $Rs.$)

Some articles were bought at $6$ for $Rs. 5$ and sold at $5$ for $Rs. 6 .$ Gain percent is