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: a man purchased 3 blankets @ rs . 100 each , 6 blankets @ rs . 150 each and two blankets at a certain rate which is now slipped off from his memory . but he remembers that the average price of the blankets was rs . 150 . find the unknown rate of two blankets ? 
Options: a ) a ) 300 , b ) b ) 350 , c ) c ) 450 , d ) d ) 470 , e ) e ) 500
a

Problem: average expenditure of a person for the first 3 days of a week is rs . 330 and for the next 4 days is rs . 420 . average expenditure of the man for the whole week is : 
Options: a ) 350 , b ) 370 , c ) 390 , d ) 430 , e ) none
b

Problem: if n is a positive integer and the product of all integers from 1 to n , inclusive , is a multiple of 690 , what is the least possible value of n ? 
Options: a ) 10 , b ) 11 , c ) 12 , d ) 13 , e ) 23

e