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 businessman earns $28800 in December, thus decreasing his average annual (January to December) earnings by $1300. His average annual earnings would be
Source: CMAT Preparation

 Option A: $29000

 Option B: $33500

 Option C: $40200

 Option D: $41000

 Option E: $43100
Option E

Question: A gambler bought $3,000 worth of chips at a casino in denominations of $20 and $100. That evening, the gambler lost 13 chips, and then cashed in the remainder. If the number of $20 chips lost was 3 more or 3 less than the number of $100 chips lost, what is the largest amount of money that the gambler could have received back?

 Option A: $2,040

 Option B: $2,120

 Option C: $2,240

 Option D: $1,920

 Option E: $1,400
Option C

Question: In a store 6 different CDs are there. If John can buy 2 CDs, how many cases that he can buy are there?

 Option A: 12

 Option B: 15

 Option C: 18

 Option D: 21

 Option E: 24

Option B