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.

[EX Q]: Question: The average of first ten prime numbers which are odd is?

 Option A: 15.5

 Option B: 15.7

 Option C: 15.2

 Option D: 15.8

 Option E: 15.1
[EX A]: Option D

[EX Q]: Question: The length of a room is 7 m and width is 4.75 m. What is the cost of paying the floor by slabs at the rate of Rs. 900 per sq. metre.

 Option A: 25650

 Option B: 25750

 Option C: 26550

 Option D: 26750

 Option E: 29925
[EX A]: Option E

[EX Q]: Question: A gambler has won 40% of his 40 poker games for the week so far. If, all of a sudden, his luck changes and he begins winning 70% of the time, how many more games must he play to end up winning 60% of all his games for the week?

 Option A: 50

 Option B: 60

 Option C: 70

 Option D: 80

 Option E: 90
[EX A]:
Option D