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'.

Q: 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

A: e
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Q: Problem: a shopkeeper sells 500 metres of cloth for rs . 18000 at a loss of rs . 5 per metre . find his cost price for one metre of cloth ? 
Options: a ) 12 , b ) 27 , c ) 29 , d ) 50 , e ) 41

A: e
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Q: Problem: the population of a town is 10000 . it increases annually at the rate of 25 % p . a . what will be its population after 2 years ? 
Options: a ) 14000 , b ) 14400 , c ) 14500 , d ) 15625 , e ) 14700

A:
d
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