Problema Solution

A contest offers 20 prizes.The first prize is 10000 pesos and each successive prize is 300 pesos less than the preceeding prize. What is the value of the 20th prize. What is the total amouny of prize money that is being awarded?

Answer provided by our tutors

first prize is: 10,000


2nd price is: 10,000 - 300


3rd price is: 10,000 - 2*300


4th price is: 10,000 - 3*300


and so on


20th prize will be: 10,000 - 19*300 = 4,300 pesos


the total amount of money being awarded is:


4,300 + 4,300 + 300 + ....+ 4,300 + 19*300 =


= 4,300*20 + 300(1 + 2 + 3 + ... + 19) =


= 4,300*20 + 300*19(19 + 1)/2 =


= 143,000 pesos is the total amouny of prize money that is being awarded.