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 worker earns $ 20 on the first day and spends $ 15 on the second day. the worker earns $ 20 on the third day and spends $ 15 on the fourth day. if this pattern continues, on which day will the worker first reach a net total of $ 80 ?
Options: a. 24, b. 25, c. 27, d. 30, e. 32
[A]: b

[Q]: Problem: a thief is spotted by a policeman from a distance of 150 meters. when the policeman starts the chase, the thief also starts running. if the speed of the thief be 8 km / hr and that of the policeman 10 km / hr, how far the thief will have run before he is overtaken ?
Options: a. 350 m, b. 200 m, c. 400 m, d. 600 m, e. none of them
[A]: d

[Q]: Problem: if 1 / 5 th of a number decreased by 5 is 5, then the number is
Options: a. 25, b. 50, c. 60, d. 75, e. none
[A]:
b