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'.
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Question: Problem: a , b and c enter into partnership . a invests some money at the beginning , b invests double the amount after 6 months , and c invests thrice the amount after 8 months . if the annual gain be rs . 21000 . a ' s share is ? 
Options: a ) 2999 , b ) 2778 , c ) 7000 , d ) 2889 , e ) 6612

Answer: c


Question: Problem: on selling 17 balls at rs . 720 , there is a loss equal to the cost price of 5 balls . the cost price of a ball is 
Options: a ) 20 , b ) 30 , c ) 40 , d ) 50 , e ) 60

Answer: e


Question: Problem: find the simple interest on $ 10000 at 8 % per annum for 12 months ? 
Options: a ) $ 410 , b ) $ 500 , c ) $ 650 , d ) $ 800 , e ) $ 1000

Answer:
d