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: 10 is added to a certain number , the sum is multiplied by 2 , the product is divided by 2 and 2 is subtracted from the quotient . the remainder left is half of 88 . what is the number ? 
Options: a ) 21 , b ) 20 , c ) 25 , d ) 36 , e ) 45

Answer: d


Question: Problem: in a group of ducks and cows , the total number of legs are 22 more than twice the no . of heads . find the total no . of buffaloes . 
Options: a ) 11 , b ) 12 , c ) 13 , d ) 15 , e ) 16

Answer: a


Question: Problem: in a group of 130 people , 90 have an age of more 30 years , and the others have an age of less than 20 years . if a person is selected at random from this group , what is the probability the person ' s age is less than 20 ? 
Options: a ) 0.31 , b ) 0.55 , c ) 0.65 , d ) 0.75 , e ) 0.85

Answer:
a