The task is to generate the correct answer for a given math problem.

Q: 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 ?

A: 12
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Q: Problem: at what rate percent on simple interest will rs . 750 amount to rs . 900 in 8 years ?

A: 2.5 %
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Q: Problem: how many 2 - inch by 3 - inch rectangular tiles are required to tile this shaded region ?

A:
1,500 +'
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