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'.

Q: Problem: cost is expressed by the formula tb ^ 4 . if b is doubled , the new cost is what percent of the original cost ? 
Options: a ) 200 , b ) 600 , c ) 800 , d ) 1600 , e ) 50

A: d
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Q: Problem: if a number x is 10 % less than another number y and y is 10 % more than 125 , then x is equal to 
Options: a ) 143 , b ) 150 , c ) 123.75 , d ) 140.55 , e ) none

A: c
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Q: Problem: the average of 45 results is 10 . the average of first 22 of them is 15 and that of last 22 is 20 . find the 23 result ? 
Options: a ) 600 , b ) 480 , c ) 750 , d ) 650 , e ) 560

A:
e
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