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'.
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Question: Problem: what is the greatest integer m for which the number 30 ! / 10 ^ m is an integer ?
Options: a ) 7 , b ) 8 , c ) 9 , d ) 10 , e ) 11

Answer: a

Question: Problem: a cyclist rides a bicycle 7 km at an average speed of 10 km / hr and again travels 10 km at an average speed of 7 km / hr . what is the average speed for the entire trip ?
Options: a ) 7.59 , b ) 7.79 , c ) 7.99 , d ) 8.19 , e ) 8.39

Answer: c

Question: Problem: little john had $ 8.50 . he spent $ 1.25 on sweets and gave to his two friends $ 1.20 and $ 2.20 . how much money was left ?
Options: a ) $ 5.85 , b ) $ 6.85 , c ) $ 3.85 , d ) $ 2.85 , e ) $ 4.85

Answer:
c