The task is to generate the correct answer for a given math problem.
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Question: Problem: a train 200 m long can cross an electric pole in 5 sec and then find the speed of the train ?

Answer: 144

Question: Problem: the probability is 1 / 2 that a certain coin turns up heads on any given toss . if the coin is tossed 6 times , what is the probability that the coin turns up tails on at least one of the tosses ?

Answer: 63 / 64

Question: Problem: if it is assumed that 60 percent of those who receive a questionnaire by mail will respond and 900 responses are needed , what is the minimum number of questionnaires that should be mailed ?

Answer:
150