Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.

Q: Problem: a / ( b / c. in the expression above, a, b, and c are different numbers and each is one of the numbers 2, 3, or 6. what is the largest possible value of the expression ?
Options: a. 2 / 18, b. 6 / 3, c. 30 / 2, d. 18 / 2, e. 6 / 18

A: d
****
Q: Problem: john and david can finish a job together in 2 hours. if john can do the job by himself in 3 hours, what percent of the job does david do ?
Options: a. 36.33 %, b. 33.33 %, c. 39.33 %, d. 40.33 %, e. 33 %

A: b
****
Q: Problem: a manufacturer produces a certain men ' s athletic shoe in integer sizes from 8 to 17. for this particular shoe, each unit increase in size corresponds to a 1 / 4 - inch increase in the length of the shoe. if the largest size of this shoe is 10 % longer than the smallest size, how long, in inches, is the shoe in size 15 ?
Options: a. 18.25, b. 20.75, c. 22.25, d. 24.25, e. 26.75

A:
d
****