$A$ shopkeeper expects a gain of $22 \frac{1}{2} \%$ on his cost price. If in a week,his sale was of $Rs. \,392$,what was his profit? (in $Rs$)

Successive discounts of $10 \%$,$20 \%$ and $50 \%$ will be equivalent to a single discount of .......... $\%$

$A$ pair of articles was bought for $Rs. 37.40$ at a discount of $15 \%$. What must be the marked price of each of the articles?

Kamal has some apples. He sold $40\%$ more than he ate. If he sold $70$ apples,how many did he eat?

$A$ shopkeeper sells notebooks at the rate of $Rs. 457$ each and earns a commission of $4\%$. He also sells pencil boxes at the rate of $Rs. 80$ each and earns a commission of $20\%$. How much total commission will he earn in two weeks if he sells $10$ notebooks and $6$ pencil boxes a day?

$A$ shopkeeper purchased $245$ pieces of an article at $Rs. 30$ per piece. He spent $Rs. 980$ on transport and $Rs. 1470$ on packing the articles. He sold the articles at the rate of $Rs. 50$ per piece. What is the percent profit earned?