In this task, you need to answer the given multiple-choice question on the gain. Gain is the value by which to multiply the input. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Problem: the present worth of rs . 2310 due years hence , the rate of interest being 15 % per annum , is : 
Options: a ) rs . 1440 , b ) rs . 1750 , c ) rs . 1680 , d ) rs . 1840 , e ) none of these
c

Problem: a reduction of 23 % in the price of salt enables a lady to obtain 10 kgs more for rs . 100 , find the original price per kg ? 
Options: a ) s . 2.99 , b ) s . 2.4 , c ) s . 2.5 , d ) s . 2.2 , e ) s . 2.1
a

Problem: a shopkeeper sells 300 metres of cloth for rs . 9000 at a loss of rs . 6 per metre . find his cost price for one metre of cloth ? 
Options: a ) s . 59 , b ) s . 58 , c ) s . 36 , d ) s . 46 , e ) s . 13

c