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 cement mixture is composed of 3 elements. by weight, 1 / 2 of the mixture is sand, 1 / 5 of the mixture is water, and the remaining 15 pounds of the mixture is gravel. what is the weight of the entire mixture in pounds ?
Options: a. 30, b. 40, c. 50, d. 60, e. 80
[A]: c


[Q]: Problem: a card game called “ high - low ” divides a deck of 52 playing cards into 2 types, “ high ” cards and “ low ” cards. there are an equal number of “ high ” cards and “ low ” cards in the deck and “ high ” cards are worth 2 points, while “ low ” cards are worth 1 point. if you draw cards one at a time, how many ways can you draw “ high ” and “ low ” cards to earn 7 points if you must draw exactly 5 “ low ” cards ?
Options: a. 6, b. 2, c. 3, d. 4, e. 5
[A]: a


[Q]: Problem: a grocer has a sale of rs. 5255, rs. 5840, rs. 5921, rs. 6022 and rs. 6499 for 5 consecutive months. how much sale must he have in the sixth month so that he gets an average sale of rs. 5500 ?
Options: a. 3463, b. 4463, c. 5463, d. 4063, e. 5063
[A]:
b