TASK DEFINITION: You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.
PROBLEM: Question: (3x + 1) (2x - 5) = ax^2 + kx + n . What is the value of a - n + k ?

 Option A: 5

 Option B: 8

 Option C: 9

 Option D: 14

 Option E: 11

SOLUTION: Option D

PROBLEM: Question: Ajit has a certain average for 9 innings. In the tenth innings, he scores 100 runs thereby increasing his average by 8 runs. His new average is:

 Option A: 20

 Option B: 21

 Option C: 28

 Option D: 32

 Option E: None

SOLUTION: Option C

PROBLEM: Question: A coin is tossed live times. What is the probability that there is at the least one tail?

 Option A: 31/32

 Option B: 31/35

 Option C: 31/39

 Option D: 31/12

 Option E: 31/39

SOLUTION:
Option A