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: walking at 4 / 5 of her normal speed, a worker is 10 minutes later than usual in reaching her office. the usual time ( in minutes ) taken by her to cover the distance between her home and her office is
Options: a. 30, b. 35, c. 40, d. 45, e. 50
answer:
c


question:
Problem: if the population of a certain country increases at the rate of one person every 15 seconds, by how many persons does the population increase in 25 minutes ?
Options: a. 80, b. 100, c. 150, d. 240, e. 300
answer:
b


question:
Problem: an order was placed for the supply of a carpet whose breadth was 6 m and length was 1.44 times the breadth. what be the cost of a carpet whose length and breadth are 40 % more and 25 % more respectively than the first carpet. given that the ratio of carpet is rs. 45 per sq m ?
Options: a. rs. 3642.40, b. rs. 3868.80, c. rs. 4216.20, d. rs. 4082.40, e. none of these
answer:

d