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: Calculate the sum of first 60 natural numbers.

 Option A: 1839

 Option B: 2830

 Option C: 1830

 Option D: 1831

 Option E: 1835

SOLUTION: Option C

PROBLEM: Question: A man rows his boat 85 km downstream and 45 km upstream, taking 2 1/2 hours each time. Find the speed of the stream?

 Option A: 6 kmph

 Option B: 9 kmph

 Option C: 3 kmph

 Option D: 8 kmph

 Option E: 1 kmph

SOLUTION: Option D

PROBLEM: Question: Which of the following is NOT a factor of 10! ?

 Option A: 1440

 Option B: 625

 Option C: 160

 Option D: 80

 Option E: 50

SOLUTION:
Option B