instruction:
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.
question:
Problem: two trains of equal are running on parallel lines in the same direction at 45 km / hr and 36 km / hr. the faster train passes the slower train in 36 sec. the length of each train is ?
Options: a. 45, b. 88, c. 66, d. 55, e. 22
answer:
a

question:
Problem: a couple spent $ 211.20 in total while dining out and paid this amount using a credit card. the $ 211.20 figure included a 20 percent tip which was paid on top of the price which already included a sales tax of 10 percent on top of the price of the food. what was the actual price of the food before tax and tip ?
Options: a. $ 120, b. $ 140, c. $ 150, d. $ 160, e. $ 180
answer:
d

question:
Problem: harry started a 4 - mile hike with a full 6 - cup canteen of water and finished the hike in 2 hours with 1 cup of water remaining in the canteen. if the canteen leaked at the rate of 1 cup per hour and harry drank 1 cups of water during the last mile, how many cups did he drink per mile during the first 3 miles of the hike ?
Options: a. 1 / 3, b. 2 / 3, c. 3 / 4, d. 5 / 4, e. 4 / 3
answer:
b