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'.

Problem: sum of two numbers is 63 . their difference is 1 / 8 of their sum . their l . c . m is 
Options: a ) 231 , b ) 153 , c ) 351 , d ) 345 , e ) 355
c

Problem: the mean of 50 observations was 36 . it was found later that an observation 48 was wrongly taken as 23 . the corrected new mean is : 
Options: a ) 36.5 , b ) 35 , c ) 34 , d ) 33 , e ) 32.5
a

Problem: 2 / [ ( 1 / 0.03 ) + ( 1 / 0.37 ) ] = ? 
Options: a ) 0.004 , b ) 0.05555 , c ) 2.775 , d ) 3.6036 , e ) 36.036

b