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

[EX Q]: Problem: at the faculty of aerospace engineering , 312 students study random - processing methods , 232 students study scramjet rocket engines and 112 students study them both . if every student in the faculty has to study one of the two subjects , how many students are there in the faculty of aerospace engineering ? 
Options: a ) 424 . , b ) 428 . , c ) 430 . , d ) 432 . , e ) 436
[EX A]: d

[EX Q]: Problem: in a school 10 % of the boys are same in number as 1 / 3 th of the girls . what is the ratio of boys to the girls in the school ? 
Options: a ) 5 : 2 , b ) 2 : 3 , c ) 10 : 3 , d ) 3 : 7 , e ) 2 : 5
[EX A]: c

[EX Q]: Problem: a 70 kg metal bar made of alloy of tin and silver lost 7 kg of its weight in the water . 10 kg of tin loses 1.375 kg in the water ; 5 kg of silver loses 0.375 kg . what is the ratio of tin to silver in the bar ? 
Options: a ) 1 / 4 , b ) 2 / 5 , c ) 1 / 2 , d ) 3 / 5 , e ) 2 / 3
[EX A]:
e