TASK DEFINITION: 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.
PROBLEM: Problem: if the simple interest on a certain sum of money for 6 years is one – fifth of the sum, then the rate of interest per annum is
Options: a. 3.3 %, b. 7.2 %, c. 6.1 %, d. 5.0 %, e. 3.1 %

SOLUTION: a

PROBLEM: Problem: a certain protective additive increases from 50 days to 60 days the time between required maintenance checks on an industrial vehicle. by what percent is the time between maintenance checks increased by using the additive ?
Options: a. 25 %, b. 33 1 / 3 %, c. 50 %, d. 66 2 / 3 %, e. 20 %

SOLUTION: e

PROBLEM: Problem: a can do a piece of work in 4 days. b can do it in 7 days. with the assistance of c they completed the work in 2 days. find in how many days can c alone do it ?
Options: a. 22 days, b. 28 / 3 days, c. 67 days, d. 17 / 5 days, e. 18 days

SOLUTION:
b