A shopkeeper sells a badminton racket, whose marked price is $Rs.\, 30$, at a discount of $15 \%$ and gives a shuttle cock costing $Rs.$ $1.50$ free with each racket. Even then he makes a profit of $20\%.$ His cost price per racket is (in $Rs$)
$19.75$
$20$
$21$
$21.25$
A businessman allows a discount of $10 \%$ on the marked price. What percent above the cost price must he mark his goods to make a profit of $17 \% ?$
A trader purchase a wrist watch and a pendulum for $Rs.$ $390.$ He sells them making a profit of $10 \%$ on the watch and $15 \%$ on the pendulum. He earns a profit of $Rs$. $51.50 .$ The difference between the original prices of the pendulum and the watch is equal to? (in $Rs.$)
An article is marked for sale at $Rs.$ $504 .$ The shopkeeper gives a discount of $5 \%$ on the sale price and still earns a profit of $20 \% .$ What could be the purchase price of the article? (in $Rs.$)
Present age of Bob is equal to Abby's age $8\, years$ ago. Four years hence, the respective ratio between Bob's age and Abby's age will be $4: 5$ at that time. What is Bob's present age? (in $years$)
Vijay sold a watch at a gain of $5 \%$. Had he sold it for $Rs.\, 72$ more, he would have gained $13 \%$. Find out the cost price of the watch. (in $Rs.$)