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: a man has rs . 400 in the denominations of one - rupee notes , 5 - rupee notes and 10 rupee notes . the number of notes of each denomination is equal . what is the total number of notes that he has ?
Options: a ) 45 , b ) 60 , c ) 75 , d ) 90 , e ) 95
[EX A]: c

[EX Q]: Problem: the average marks of a class of 40 students is 44 and that of another class of 45 students is 70 . find the average marks of all the students ?
Options: a ) 52.6 , b ) 52.4 , c ) 52.1 , d ) 69.5 , e ) 52.9
[EX A]: d

[EX Q]: Problem: the average weight of a class is x pounds . when a new student weighing 70 pounds joins the class , the average decreases by 1 pound . in a few months the student ' s weight increases to 110 pounds and the average weight of the class becomes x + 4 pounds . none of the other students ' weights changed . what is the value of x ?
Options: a ) 26 , b ) 86 , c ) 88 , d ) 90 , e ) 92
[EX A]:
a