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.
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Question: Question: A mixture contains alcohol and water in the ratio 4 : 3. If 5 litres of water is added to the mixture, the ratio becomes 4: 5. Find the quantity of alcohol in the given mixture

 Option A: 15 litres

 Option B: 10 litres

 Option C: 30 litres

 Option D: 22 litres

 Option E: 8 litres

Answer: Option B


Question: Question: Total dinning bill for 8 people was $211.00.If they add 15% tip and divided the bill evenly ,approximate.What was each persons find share

 Option A: $30.14

 Option B: 45.14

 Option C: 34.66

 Option D: 32.29

 Option E: 30.33

Answer: Option E


Question: Question: If D is the product of all positive integers less than 31, than what is the greatest integer k for which D/18^k is an integer?

 Option A: 3

 Option B: 6

 Option C: 7

 Option D: 14

 Option E: 26

Answer:
Option C