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.

Question: A and B started a partnership business investing Rs. 20,000 and Rs. 15,000 respectively. C joined them with Rs. 20,000 After six months. Calculate B's share in total profit of Rs. 25,000 earned at the end of 2 years from the starting of the business?

 Option A: 7500

 Option B: 8500

 Option C: 9000

 Option D: 8000

 Option E: None of these
Option A

Question: The average marks of a class of 35 students is 45 and that of another class of 55 students is 65. Find the average marks of all the students?

 Option A: 52.6

 Option B: 52.4

 Option C: 52.1

 Option D: 57

 Option E: 52.9
Option D

Question: One-third of 600 is what percent of 120 ?

 Option A: 313.2

 Option B: 30.1

 Option C: 12.24

 Option D: None of these

 Option E: 166.6

Option E