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: a car traveled 80 % of the way from town x to town y at an average speed of 80 mph . the car traveled at an average speed of v mph for the remaining part of the trip . the average speed for the entire trip was 50 mph . what is v in mph ? 
Options: a ) 25 , b ) 35 , c ) 45 , d ) 55 , e ) 20

A: e
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Q: Problem: if a * b * c = ( √ ( a + 2 ) ( b + 3 ) ) / ( c + 1 ) , find the value of 6 * 15 * 3 . 
Options: a ) 8 , b ) 5 , c ) 11 , d ) 3 , e ) 4

A: d
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Q: Problem: if w / x = 5 / 7 and w / y = 4 / 7 , then ( x + y ) / y = 
Options: a ) 1 / 2 , b ) 7 / 3 , c ) 6 / 7 , d ) 1 / 5 , e ) 11 / 13

A:
b
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