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: For positive integers x and z, which of the following can be written as z^2?

 Option A: x^2+1

 Option B: x^2-1

 Option C: x^2-24

 Option D: x^2+11

 Option E: x^2-11

Answer: Option D


Question: Question: P is three times as fast as Q and working together, they can complete a work in 12 days. In how many days can Q alone complete the work?

 Option A: 11 days

 Option B: 16 days

 Option C: 13 days

 Option D: 15 days

 Option E: 19 days

Answer: Option B


Question: Question: A motorcyclist goes from Bombay to Pune, a distance of 192 kms at an average of 32 kmph speed. Another man starts from Bombay by car 2 ½ hours after the first, and reaches Pune ½ hour earlier. What is the ratio of the speed of the motorcycle and the car?

 Option A: 1:2

 Option B: 1:7

 Option C: 1:9

 Option D: 1:5

 Option E: 1:1

Answer:
Option A