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 lady bought five books namely A,B,C,D,E to distribute her 7 friends. How many ways she can distribute books?

 Option A: 7^3

 Option B: 7^4

 Option C: 7^5

 Option D: 7^6

 Option E: 7^2

A: Option C
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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
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Q: Question: When 35 per cent of a number is added to another number,the second number increases by its 20 per cent. What is the ratio between the second number and the first number?

 Option A: 4 : 7

 Option B: 7 : 4

 Option C: 8 : 5

 Option D: Data inadequate

 Option E: None of these

A:
Option B
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