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: calculate how many seconds it will take for 4 bells to toll together again , given that they begin to toll together respectively at the intervals of 9 , 10 , 14 and 18 seconds . ? 
Options: a ) 636 , b ) 631 , c ) 633 , d ) 610 , e ) 630

Answer: e


Question: Problem: in a restaurant , the profit is 120 % of the cost . if the cost increases by 12 % but the selling price remains constant , approximately what percentage of the selling price is the profit ? 
Options: a ) 30 % , b ) 49 % , c ) 90 % , d ) 100 % , e ) none of these

Answer: b


Question: Problem: find the simple interest on $ 3000 for 3 years at 10 % per annum ? 
Options: a ) $ 900 , b ) $ 300 , c ) $ 500 , d ) $ 600 , e ) $ 1000

Answer:
a