The task is to generate the correct answer for a given math problem.
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Question: Problem: audrey 4 hours to complete a certain job . ferris can do the same job in 3 hours . audrey and ferris decided to collaborate on the job , working at their respective rates . while audrey worked continuously , ferris took 5 breaks of equal length . if the two completed the job together in 2 hours , how many minutes long was each of ferris ’ breaks ?

Answer: 6


Question: Problem: two tains of equal lengths take 10 seconds and 15 seconds respectively to cross a telegraph post . if the length of each train be 120 metres , in what time ( in seconds ) will they cross each other travelling in opposite direction ?

Answer: 12


Question: Problem: john builds a square with a side of 12 cm from some wire . if from the same wire , he builds a rectangle with a width of 6 cm , what will be the length of the rectangle ?

Answer:
18 cm', 'b ) 19 cm', 'c ) 20 cm', 'd ) 21 cm', 'e ) none'