A sum of Rs. 700 is to be used to give seven cash prizes to students of a school for their overall academic performance. If each prize is Rs. 20 less than its preceding prize. Find the value of each of prizes.

A sum of ₹3000 is to be given in the form of 63 prizes. If the prize money is either ₹100 or ₹25. Find the number of prizes of each type.

A certain book shop has 10 dozen chemistry books, 8 dozen physics books, 10 dozen economics books. Their selling prices are Rs.80, Rs.60, Rs.40, each respectively. Using matrix algebra. Find the total value of the books in the shop.

Three persons A,B,C in order cut a pack of cards replacing them after each cut. The person who first cuts a club shall win a prize. Find the probabilities of their winning.

A certain book shop has 10 dozen chemistry books, 8 dozen physics books, 10 dozen economics books. Their selling prices are Rs. 80, Rs. 60, Rs. 40 each respectively. Using matrix algebra, find the total value of the books in the shop.

The number of ways that 12 prizes can be divided among 4 students so that each may have 3 prizes is

Ten identical mementos is made by a school to awarding 10 students for first pize winners in games . If each memento is made as shown in figure (shaded portion) its base PQRS is silver plated from the front side at the rate of RS 20 per square cm . Find the total cost of the silver plating of 10 mements . (OR = 5 cm , RQ= 6 cm , PS = 8 cm )

A sum of Rs. 1000 is invested at 8% simple interest per year. Calculate the interest at the end of each year. Do these interests 1^(st), 2^(nd) and 3^(rd) years form a AP? If so, find the total interest to be paid for 30 years making the use of this fact.