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.

[Q]: Question: A broker invested her own money in the stock market. During the first year, she increased her stock market wealth by 40 percent. In the second year, largely as a result of a slump in the stock market, she suffered a 30 percent decrease in the value of her stock investments. What was the net increase or decrease on her overall stock investment wealth by the end of the second year?

 Option A: −5%

 Option B: −2%

 Option C: 15%

 Option D: 20%

 Option E: 80%
[A]: Option B


[Q]: Question: A boat takes 19 hours for travelling downstream from point A to point B and coming back to a point C midway between A and B. If the velocity of the stream is 4 kmph and the speed of the boat in still water is 14 kmph, what is the distance between A and B ?

 Option A: 160 km

 Option B: 180 km

 Option C: 200 km

 Option D: 220 km

 Option E: None
[A]: Option B


[Q]: Question: Some of 45%-intensity red paint is replaced with 25% solution of red paint such that the new paint intensity is 40%. What fraction of the original paint was replaced?

 Option A: 2/5

 Option B: 1/4

 Option C: 1/5

 Option D: 1/7

 Option E: 2/3
[A]:
Option B