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 complete a work in 6 days. A can alone can do it in 10 days. If both can together can do the work in how many days?

 Option A: 7

 Option B: 3.75

 Option C: 2

 Option D: 1

 Option E: 8
Option B

Question: In measuring the sides of a rectangle, one side is taken 6% in excess, and the other 5% in deficit. Find the error percent in the area calculated from these measurements.

 Option A: 0.11%

 Option B: 0.7%

 Option C: 0.4%

 Option D: 0.6%

 Option E: 0.8%
Option B

Question: If two numbers are in the ratio 2:3. If10 is added to both of the numbers then the ratio becomes 5:6 then find the largest number?

 Option A: 20

 Option B: 40

 Option C: 20/3

 Option D: 30

 Option E: 10

Option E