In this task, you need to provide the correct option for a given problem from the provided options.

[EX Q]: Problem: a can contains a mixture of liquids a and b is the ratio 7 : 5 . when 9 litres of mixture are drawn off and the can is filled with b , the ratio of a and b becomes 7 : 9 . how many liter e of liquid a was contained by the can initially ? 
Options: a ) 10 , b ) 20 , c ) 21 , d ) 25 , e ) 27
[EX A]: c

[EX Q]: Problem: at a garage sale , all of the items were sold at different prices . if the price of a radio sold at the garage sale was both the 15 th highest price and the 22 nd lowest price among the prices of the items sold , how many items were sold at the garage sale ? 
Options: a ) 34 , b ) 35 , c ) 36 , d ) 37 , e ) 38
[EX A]: c

[EX Q]: Problem: if 32.5 % of the 880 students at a certain college are enrolled in biology classes , how many students at the college are not enrolled in a biology class ? 
Options: a ) 110 , b ) 330 , c ) 550 , d ) 594 , e ) 880
[EX A]:
d