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: A die is rolled twice. What is the probability of getting a sum equal to 9?

 Option A: 2/3

 Option B: 2/9

 Option C: 1/3

 Option D: 1/9

 Option E: 1/10
[EX A]: Option D

[EX Q]: Question: Which of the following CANNOT be weighed using a balance scale and these unit weights: 1, 4, 7, and 10

 Option A: 13

 Option B: 15

 Option C: 17

 Option D: 19

 Option E: 21
[EX A]: Option A

[EX Q]: Question: A and B began business with Rs.3000 and Rs.4000 after 8 months, A withdraws Rs.1000 and B advances Rs.1000 more. At the end of the year, their profits amounted to Rs.630 find the share of A?

 Option A: 240

 Option B: 278

 Option C: 209

 Option D: 267

 Option E: 262
[EX A]:
Option A