In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

[EX Q]: Problem: in august , a cricket team that played 120 matches won 26 % of the games it played . after a continuous winning streak , this team raised its average to 52 % . how many matches did the team win to attain this average ? 
Options: a ) 40 , b ) 52 , c ) 65 , d ) 80 , e ) 98
[EX A]: c

[EX Q]: Problem: for any positive integer n , the sum of the first n positive integers equals n ( n + 1 ) / 2 . what is the sum of all the integers between 1 and 50 ? 
Options: a ) 1275 , b ) 1542 , c ) 985 , d ) 1024 , e ) 1125
[EX A]: a

[EX Q]: Problem: a small pool filled only with water will require an additional 600 gallons of water in order to be filled to 80 % of its capacity . if pumping in these additional 600 gallons of water will increase the amount of water in the pool by 30 % , what is the total capacity of the pool in gallons ? 
Options: a ) 1000 , b ) 1250 , c ) 1300 , d ) 1600 , e ) 2000
[EX A]:
e